Literatura académica sobre el tema "Entanglement of Gaussian states"

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Artículos de revistas sobre el tema "Entanglement of Gaussian states"

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Fukuda, Motohisa y Robert Koenig. "Typical entanglement for Gaussian states". Journal of Mathematical Physics 60, n.º 11 (1 de noviembre de 2019): 112203. http://dx.doi.org/10.1063/1.5119950.

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Kraus, B., G. Giedke, M. Lewenstein y J. I. Cirac. "Entanglement properties of Gaussian states". Fortschritte der Physik 51, n.º 45 (7 de mayo de 2003): 305–12. http://dx.doi.org/10.1002/prop.200310043.

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JIANG, LI-ZHEN. "ENTANGLEMENT BOUNDS FOR A FAMILY OF TWO-MODE GAUSSIAN STATES". International Journal of Quantum Information 02, n.º 02 (junio de 2004): 273–83. http://dx.doi.org/10.1142/s0219749904000201.

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I study a family of bipartite quantum Gaussian states with three parameters, calculate Gaussian entanglement of formation analytically and the upper bound of relative entropy of entanglement, compare them with the coherent information of the states. Based on the numerical observation, I determine the relative entropy of entanglement and distillable entanglement of the states with infinitive squeezing.
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Marian, P. y T. A. Marian. "Gaussian entanglement of symmetric two-mode Gaussian states". European Physical Journal Special Topics 160, n.º 1 (julio de 2008): 281–89. http://dx.doi.org/10.1140/epjst/e2008-00731-x.

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LUPO, COSMO, STEFANO MANCINI, PAOLO FACCHI, GIUSEPPE FLORIO y SAVERIO PASCAZIO. "ENTANGLEMENT FRUSTRATION IN MULTIMODE GAUSSIAN STATES". International Journal of Geometric Methods in Modern Physics 09, n.º 02 (marzo de 2012): 1260022. http://dx.doi.org/10.1142/s0219887812600225.

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Bipartite entanglement between two parties of a composite quantum system can be quantified in terms of the purity of one party and there always exists a pure state of the total system that maximizes it (and minimizes purity). When many different bipartitions are considered, the requirement that purity be minimal for all bipartitions gives rise to the phenomenon of entanglement frustration. This feature, observed in quantum systems with both discrete and continuous variables, can be studied by means of a suitable cost function whose minimizers are the maximally multipartite-entangled states (MMES). In this paper we extend the analysis of multipartite entanglement frustration of Gaussian states in multimode bosonic systems. We derive bounds on the frustration, under the constraint of finite mean energy, in the low- and high-energy limits.
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Giedke, G., J. Eisert, J. I. Cirac y M. B. Plenio. "Entanglement transformations of pure Gaussian states". Quantum Information and Computation 3, n.º 3 (mayo de 2003): 211–33. http://dx.doi.org/10.26421/qic3.3-3.

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We present a theory of entanglement transformations of Gaussian pure states with local Gaussian operations and classical communication. This is the experimentally accessible set of operations that can be realized with optical elements such as beam splitters, phase shifts and squeezers, together with homodyne measurements. We provide a simple necessary and sufficient condition for the possibility to transform a pure bipartite Gaussian state into another one. We contrast our criterion with what is possible if general local operations are available.
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Zhang, Kun, Jietai Jing, Nicolas Treps y Mattia Walschaers. "Maximal entanglement increase with single-photon subtraction". Quantum 6 (2 de mayo de 2022): 704. http://dx.doi.org/10.22331/q-2022-05-02-704.

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Entanglement is an indispensable quantum resource for quantum information technology. In continuous-variable quantum optics, photon subtraction can increase the entanglement between Gaussian states of light, but for mixed states the extent of this entanglement increase is poorly understood. In this work, we use an entanglement measure based the Rényi-2 entropy to prove that single-photon subtraction increases bipartite entanglement by no more than log 2. This value coincides with the maximal amount of bipartite entanglement that can be achieved with one photon. The upper bound is valid for all Gaussian input states, regardless of the number of modes and the purity.
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Filippov, Sergey y Alena Termanova. "Superior Resilience of Non-Gaussian Entanglement against Local Gaussian Noises". Entropy 25, n.º 1 (30 de diciembre de 2022): 75. http://dx.doi.org/10.3390/e25010075.

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Entanglement distribution task encounters a problem of how the initial entangled state should be prepared in order to remain entangled the longest possible time when subjected to local noises. In the realm of continuous-variable states and local Gaussian channels it is tempting to assume that the optimal initial state with the most robust entanglement is Gaussian too; however, this is not the case. Here we prove that specific non-Gaussian two-mode states remain entangled under the effect of deterministic local attenuation or amplification (Gaussian channels with the attenuation factor/power gain κi and the noise parameter μi for modes i=1,2) whenever κ1μ22+κ2μ12<14(κ1+κ2)(1+κ1κ2), which is a strictly larger area of parameters as compared to where Gaussian entanglement is able to tolerate noise. These results shift the “Gaussian world” paradigm in quantum information science (within which solutions to optimization problems involving Gaussian channels are supposed to be attained at Gaussian states).
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Takahashi, Hiroki, Jonas S. Neergaard-Nielsen, Makoto Takeuchi, Masahiro Takeoka, Kazuhiro Hayasaka, Akira Furusawa y Masahide Sasaki. "Entanglement distillation from Gaussian input states". Nature Photonics 4, n.º 3 (7 de febrero de 2010): 178–81. http://dx.doi.org/10.1038/nphoton.2010.1.

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Huang, Youyi y Lu Wei. "Second-order statistics of fermionic Gaussian states". Journal of Physics A: Mathematical and Theoretical 55, n.º 10 (14 de febrero de 2022): 105201. http://dx.doi.org/10.1088/1751-8121/ac4e20.

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Abstract We study the statistical behavior of entanglement in quantum bipartite systems over fermionic Gaussian states as measured by von Neumann entropy and entanglement capacity. The focus is on the variance of von Neumann entropy and the mean entanglement capacity that belong to the so-defined second-order statistics. The main results are the exact yet explicit formulas of the two considered second-order statistics for fixed subsystem dimension differences. We also conjecture the exact variance of von Neumann entropy valid for arbitrary subsystem dimensions. Based on the obtained results, we analytically study the numerically observed phenomena of Gaussianity of von Neumann entropy and linear growth of average capacity.
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Tesis sobre el tema "Entanglement of Gaussian states"

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Buono, Daniela. "Quantumness of gaussian and non-gaussian states in the optical domain". Doctoral thesis, Universita degli studi di Salerno, 2013. http://hdl.handle.net/10556/827.

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2011 - 2012
The Dissertation Quantumness of Gaussian and non-Gaussian states in the op- tical domain collects my personal both theoretical and experimental contribu- tions, in the context of the Quantum Information theory in continuous variables (cv). In this context, the research focused on the analysis of the quantum prop- erties of bipartite states of electromagnetic radiation. The Dissertation contains, rst, the study of the main possible quantum cor- relations between two modes of the electromagnetic eld. Particular attention has been devoted to the analysis of the di¤erent forms of non-locality present in quantum mechanics. Second, it shows the analysis of how the presence of quantum properties in bipartite states a¤ects the performance of these states, when they are used as resources in quantum protocols. In particular, the cv teleportation protocol was used as a reference to test the goodness of results. The quantum resources can be divided in two main classes: Gaussian re- sources and non-Gaussian ones. My research activity has been strucured in which way to be able to proceed, in parallel, to the analysis of both classes. Gaussian resoures.To assess the presence of entanglement in a quantum system it is possible to refer to the many criteria proposed in the literature. In the Dissertation it is reported the study of some main criteria generally used for Gaussian bipartite mixed states. This study has allowed us to establish a hierarchy very useful for the evaluation of the entanglement. Then we have dis- cussed and experimentally analyzed the e¤ects of the transmission over a lossy channel on the quantumness of bipartite Gaussian states, focusing our analysis on the states generated by a type-II optical parametric oscillator (OPO). Even- tually it is reported the study of the Bell s inequality in terms of purity and entanglement for a bipartite Gaussian state, desribed by a symmetric covari- ance matrix..It allows to investigate how the "quantumness" owned by a state, established by the violation of Bell s inequality, is related to the purity of the state and to the entanglement. Non-Gaussian resources. The study of non-Gaussian resources is mainly related to a particular class of states: the squeezed Bell states. All the analy- sis carried out to date show that these states are one of the best possible re- sources for e¢ cient BKV quantum teleportation protocol. This is con rmed by two additional theoretical tests presented in the Dissertation. In fact, squeezed Bell states maximize the violation of Bell s inequality with respect to all other (Gaussian and non-Gaussian) states obtained from the same class. So they represent the most non-local resource among all those considered (for example, the squeezed photon number states, the photon subtracted squeezed states, the photon added states, the squeezed vacuum states). Moreover, as demonstrated in the course of the Dissertation, squeezed Bell states are the best resource for teleportation of a coherent state, even after having undergone a process of en- tanglement swapping. The result is compared with that provided by the other main quantum swapped resources of the same class. As a consequence of the positive results obtained from the tests, it was designed a scheme that allows the experimental production of squeezed Bell states. It is then evaluated its experimental feasibility both in ideal and realistic conditions obtaining very encouraging results. Finally, it is dealt the study (it is at a very preliminary stage) of a non-Gaussian state produced by a sub-threshold OPO, when there are uctuations of some parameters of the optical device (amplitude and phase of the pump, etc..) at the aim to nd a new strategy for the generation of non-Gaussian resources. [edited by author]
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Strobel, Helmut [Verfasser] y Markus K. [Akademischer Betreuer] Oberthaler. "Fisher Information and entanglement of non-Gaussian spin states / Helmut Strobel ; Betreuer: Markus K. Oberthaler". Heidelberg : Universitätsbibliothek Heidelberg, 2016. http://d-nb.info/1180610423/34.

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Gagatsos, Christos. "Gaussian deterministic and probabilistic transformations of bosonic quantum fields: squeezing and entanglement generation". Doctoral thesis, Universite Libre de Bruxelles, 2014. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209146.

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The processing of information based on the generation of common quantum optical states (e.g. coherent states) and the measurement of the quadrature components of the light field (e.g. homodyne detection) is often referred to as continuous-variable quantum information processing. It is a very fertile field of investigation, at a crossroads between quantum optics and information theory, with notable successes such as unconditional continuous-variable quantum teleportation or Gaussian quantum key distribution. In quantum optics, the states of the light field are conveniently characterized using a phase-space representation (e.g. Wigner function), and the common optical components effect simple affine transformations in phase space (e.g. rotations). In quantum information theory, one often needs to determine entropic characteristics of quantum states and operations, since the von Neuman entropy is the quantity at the heart of entanglement measures or channel capacities. Computing entropies of quantum optical states requires instead turning to a state-space representation of the light field, which formally is the Fock space of a bosonic mode.

This interplay between phase-space and state-space representations does not represent a particular problem as long as Gaussian states (e.g. coherent, squeezed, or thermal states) and Gaussian operations (e.g. beam splitters or squeezers) are concerned. Indeed, Gaussian states are fully characterized by the first- and second-order moments of mode operators, while Gaussian operations are defined via their actions on these moments. The so-called symplectic formalism can be used to treat all Gaussian transformations on Gaussian states, including mixed states of an arbitrary number of modes, and the entropies of Gaussian states are directly linked to their symplectic eigenvalues.

This thesis is concerned with the Gaussian transformations applied onto arbitrary states of light, in which case the symplectic formalism is unapplicable and this phase-to-state space interplay becomes highly non trivial. A first motivation to consider arbitrary (non-Gaussian) states of light results from various Gaussian no-go theorems in continuous-variable quantum information theory. For instance, universal quantum computing, quantum entanglement concentration, or quantum error correction are known to be impossible when restricted to the Gaussian realm. A second motivation comes from the fact that several fundamental quantities, such as the entanglement of formation of a Gaussian state or the communication capacity of a Gaussian channel, rely on an optimization over all states, including non-Gaussian states even though the considered state or channel is Gaussian. This thesis is therefore devoted to developing new tools in order to compute state-space properties (e.g. entropies) of transformations defined in phase-space or conversely to computing phase-space properties (e.g. mean-field amplitudes) of transformations defined in state space. Remarkably, even some basic questions such as the entanglement generation of optical squeezers or beam splitters were unsolved, which gave us a nice work-bench to investigate this interplay.

In the first part of this thesis (Chapter 3), we considered a recently discovered Gaussian probabilistic transformation called the noiseless optical amplifier. More specifically, this is a process enabling the amplification of a quantum state without introducing noise. As it has long been known, when amplifing a quantum signal, the arising of noise is inevitable due to the unitary evolution that governs quantum mechanics. It was recently realized, however, that one can drop the unitarity of the amplification procedure and trade it for a noiseless, albeit probabilistic (heralded) transformation. The fact that the transformation is probabilistic is mathematically reflected in the fact that it is non trace-preserving. This quantum device has gained much interest during the last years because it can be used to compensate losses in a quantum channel, for entanglement distillation, probabilistic quantum cloning, or quantum error correction. Several experimental demonstrations of this device have already been carried out. Our contribution to this topic has been to derive the action of this device on squeezed states and to prove that it acts quite surprisingly as a universal (phase-insensitive) optical squeezer, conserving the signal-to-noise ratio just as a phase-sensitive optical amplifier but for all quadratures at the same time. This also brought into surface a paradoxical effect, namely that such a device could seemingly lead to instantaneous signaling by circumventing the quantum no-cloning theorem. This paradox was discussed and resolved in our work.

In a second step, the action of the noiseless optical amplifier and it dual operation (i.e. heralded noiseless attenuator) on non-Gaussian states has been examined. We have observed that the mean-field amplitude may decrease in the process of noiseless amplification (or may increase in the process of noiseless attenuation), a very counterintuitive effect that Gaussian states cannot exhibit. This work illustrates the above-mentioned phase-to-state space interplay since these devices are defined as simple filtering operations in state space but inferring their action on phase-space quantities such as the mean-field amplitude is not straightforward. It also illustrates the difficulty of dealing with non-Gaussian states in Gaussian transformations (these noiseless devices are probabilistic but Gaussian). Furthermore, we have exhibited an experimental proposal that could be used to test this counterintuitive feature. The proposed set-up is feasible with current technology and robust against usual inefficiencies that occur in optical experiment.

Noiseless amplification and attenuation represent new important tools, which may offer interesting perspectives in quantum optical communications. Therefore, further understanding of these transformations is both of fundamental interest and important for the development and analysis of protocols exploiting these tools. Our work provides a better understanding of these transformations and reveals that the intuition based on ordinary (deterministic phase-insensitive) amplifiers and losses is not always applicable to the noiseless amplifiers and attenuators.

In the last part of this thesis, we have considered the entropic characterization of some of the most fundamental Gaussian transformations in quantum optics, namely a beam splitter and two-mode squeezer. A beam splitter effects a simple rotation in phase space, while a two-mode squeezer produces a Bogoliubov transformation. Thus, there is a well-known phase-space characterization in terms of symplectic transformations, but the difficulty originates from that one must return to state space in order to access quantum entropies or entanglement. This is again a hard problem, linked to the above-mentioned interplay in the reverse direction this time. As soon as non-Gaussian states are concerned, there is no way of calculating the entropy produced by such Gaussian transformations. We have investigated two novel tools in order to treat non-Gaussian states under Gaussian transformations, namely majorization theory and the replica method.

In Chapter 4, we have started by analyzing the entanglement generated by a beam splitter that is fed with a photon-number state, and have shown that the entanglement monotones can be neatly combined with majorization theory in this context. Majorization theory provides a preorder relation between bipartite pure quantum states, and gives a necessary and sufficient condition for the existence of a deterministic LOCC (local operations and classical communication) transformation from one state to another. We have shown that the state resulting from n photons impinging on a beam splitter majorizes the corresponding state with any larger photon number n’ > n, implying that the entanglement monotonically grows with n, as expected. In contrast, we have proven that such a seemingly simple optical component may have a rather surprising behavior when it comes to majorization theory: it does not necessarily lead to states that obey a majorization relation if one varies the transmittance (moving towards a balanced beam splitter). These results are significant for entanglement manipulation, giving rise in particular to a catalysis effect.

Moving forward, in Chapter 5, we took the step of introducing the replica method in quantum optics, with the goal of achieving an entropic characterization of general Gaussian operations on a bosonic quantum field. The replica method, a tool borrowed from statistical physics, can also be used to calculate the von Neumann entropy and is the last line of defense when the usual definition is not practical, which is often the case in quantum optics since the definition involves calculating the eigenvalues of some (infinite-dimensional) density matrix. With this method, the entropy produced by a two-mode squeezer (or parametric optical amplifier) with non-trivial input states has been studied. As an application, we have determined the entropy generated by amplifying a binary superposition of the vacuum and an arbitrary Fock state, which yields a surprisingly simple, yet unknown analytical expression. Finally, we have turned to the replica method in the context of field theory, and have examined the behavior of a bosonic field with finite temperature when the temperature decreases. To this end, information theoretical tools were used, such as the geometric entropy and the mutual information, and interesting connection between phase transitions and informational quantities were found. More specifically, dividing the field in two spatial regions and calculating the mutual information between these two regions, it turns out that the mutual information is non-differentiable exactly at the critical temperature for the formation of the Bose-Einstein condensate.

The replica method provides a new angle of attack to access quantum entropies in fundamental Gaussian bosonic transformations, that is quadratic interactions between bosonic mode operators such as Bogoliubov transformations. The difficulty of accessing entropies produced when transforming non-Gaussian states is also linked to several currently unproven entropic conjectures on Gaussian optimality in the context of bosonic channels. Notably, determining the capacity of a multiple-access or broadcast Gaussian bosonic channel is pending on being able to access entropies. We anticipate that the replica method may become an invaluable tool in order to reach a complete entropic characterization of Gaussian bosonic transformations, or perhaps even solve some of these pending conjectures on Gaussian bosonic channels.


Doctorat en Sciences de l'ingénieur
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Quinn, Niall. "Gaussian non-classical correlations in bipartite dissipative continuous variable quantum systems". Thesis, University of St Andrews, 2015. http://hdl.handle.net/10023/6915.

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This thesis probes the usefulness of non-classical correlations within imperfect continuous variable decoherent quantum systems. Although a consistent function and practical usefulness of these correlations is largely unknown, it is important to examine their characteristics in more realistic dissipative systems, to gain further insight into any possible advantageous behaviour. A bipartite separable discordant state under the action of controlled loss on one subsystem was considered. Under these conditions the Gaussian quantum discord not only proved to be robust against loss, but actually improves as loss is intensified. Harmful imperfections which reduce the achievable level of discord can be counteracted by this controlled loss. Through a purification an explanation of this effect was sought by considering system-environment correlations, and found that a flow of system-environment correlations increases the quantumness of the state. Entanglement recovery possibilities were discussed and revealed the importance of hidden quantum correlations along bi-partitions across the discordant state and a classically prepared "demodulating" system, acting in such a way as to partially cancel the entanglement preventing noise. Entanglement distribution by separable states was studied by a similar framework, in an attempt to explain the emergence of quantum entanglement by a specific flow of correlations in the globally pure system. Discord appears to play a less fundamental role compared to the qubit version of the protocol. The strengthening of non-classical correlations can be attributed to a flow of classical and quantum correlations. This work proves that discord can be created in unique ways and, in select circumstances, can act to counteract harmful imperfections in the apparatus. Due to this advantageous behaviour discord indeed may ultimately aid in more applicable "real world" applications, which are by definition decoherent.
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Missori, Ricardo José. "Análise e geração de emaranhamento em sistemas de variáveis discreta e continua via átomos". [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/278170.

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Orientadores: Kyoko Furuya e Marcos César de Oliveira
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin
Made available in DSpace on 2018-08-14T10:42:52Z (GMT). No. of bitstreams: 1 Missori_RicardoJose_D.pdf: 12608973 bytes, checksum: 25d2abc254d2688f7a4225e0cd2bc6aa (MD5) Previous issue date: 2009
Resumo: Nesta tese, apresentamos dois resultados para a geração de emaranhamento, ambos envolvendo a interação entre átomos e radiação. Na primeira parte, propomos um esquema para geração de estados emaranhados envolvendo os estados eletrônicos de dois íons separados espacialmente, cada qual aprisionado em uma cavidade. Um átomo propagante, que cruza essas cavidades, é responsável pela geração de estados emaranhados do tipo Bell entre os dois íons. Mostramos que para tempos específicos de interação, a geração dos estados emaranhados é não-probabilística. Propostas de átomo e íons, candidatos a implementação do esquema experimental, também são apresentadas. Já segunda parte deste trabalho, investigamos um modelo para a interação de dois campos quânticos ortogonalmente polarizados com uma nuvem de átomos de quatro níveis do tipo-X. Consideramos, para nosso esquema, situações físicas onde os átomos funcionam efetivamente como sendo de dois níveis. Assim, dentro de uma aproximação linearizada do campo, nosso Hamiltoniano efetivo bilinear, que representa a interação átomos-campo, passa a depender da diferença de população entre os dois níveis do ensemble de átomos. Após uma medida condicionada nos átomos, mostramos que os dois modos do campo ficam em estados emaranhados não-Gaussianos, diferentemente do que foi considerado em alguns trabalhos recentes na literatura que abordamos. Como a compressão abaixo do limite de ruído na polarização linear pode ser usada como indicadora de emaranhamento na polarização circular, nós podemos usar a variância das quadraturas, combinada com o critério de inseparabilidade para variáveis contínuas, para complementar o nosso estudo sobre o esquema experimental.
Abstract: In this thesis, we present two results of entanglement generation, both involving atom-radiation interaction. In the first part, we consider a scheme for generation of entangled states involving electronic states of two distant ions, each one placed in a cavity. A flying atom, that crosses these cavities, is responsible for the generation of entangled states of the Bell-type between the two ions. We show that for specific times of interaction, the entangled states are generated and in a non-probabilistic way. We also present a realistic proposal of candidates for atoms and ions for an experimental implementation of this scheme. In the second part of this work, we investigate a model for the interaction of two orthogonally polarized quantum fields with a cloud of X-like four-level atoms. We consider, in our scheme, a physical situation where the atoms act effectively like two-level atoms. Thus, in a linearized approximation for the field, we derive a bilinear effective Hamiltonian representing the atom-field interaction, which depends on the difference of population between the ensemble of two-level atoms. After a conditional measurement in the atomic system, we show that the two field modes ends up in a non-Gaussian entangled states, differently from what has been considered in some recent works in the literature. Since the squeezing below the noise limit in the linear polarization can be used as an indicator of entanglement in the circular polarization, we can use the variances in the quadratures, combined with the inseparability criterion for continuum variables, to complement our study of the experimental scheme.
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Física
Doutor em Ciências
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Menu, Raphaël. "Gaussian-state approaches to quantum spin systems away from equilibrium". Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEN036.

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Que se passe-t-il quand un système quantique à N corps est brutalement amené loin de son état d’équilibre ? Vers quelle sorte d’état relaxe-t-il et quelle information peut-on extraire de sa dynamique ? Fournir des réponses à ses questions est un problème difficile qui a suscité l’intérêt de toute une communauté de physiciens. Cependant, le coût numérique important requis pour étudier le comportement de ces systèmes, en particulier pour de grandes tailles, a motivé le développement de méthodes numériques et théoriques de pointes. Cette thèse s’inscrit dans la continuité de ces efforts en proposant un ensemble de méthodes basées sur une représentation en termes d’une théorie de champs Gaussiens afin d’étudier l’évolution des systèmes de spins. Plus particulièrement,ces méthodes sont appliquées `a plusieurs modèles inspirés par les expériences d’atomes froids simulant le comportement de systèmes de spins avec un accent particulier sur l’étude des phénomènes de localisations. Cette thèse présente donc des résultats mettant en évidence l’émergence de la localisation dans des systèmes sans désordre par un effet d’interférence appelé cage d’Aharonov-Bohm ; ainsi qu’une dynamique explorant un riche spectre allant de la diffusion balistique`a la localisation, en passant par la diffusion anormale, cela dans un modèle d’Ising quantique avec désordre géométrique — ce dernier exemple présence un scénario bien plus riche que celui offert par la dynamique des particules libres dans un milieu désordonné. Enfin, nous avons exploré la possibilité pour les approches gaussiennes de décrire la dynamique de systèmes interagissant et leur relaxation vers des états thermiques
What happens when a quantum many-body system is brutally driven away fromequilibrium ? Toward which kind of states does it relax and what informationcan one extract from the resulting dynamics ? Providing answers to these questionsis a challenging problem that spured the interest of a whole community ofphysicists. However, the numerical cost required to investigate the behaviour ofthese systems, particularly for large system sizes, motivated the development ofcutting-edge numerical and theoretical techniques.This thesis aims at contributing to these efforts by proposing a set of methodsbased on a representation of the systems in terms of a Gaussian field theory, withthe purpose of studying the evolution of spin systems. More specifically, thesemethods are applied to several models inspired by cold-atoms experiments simulatingthe behaviour of spin systems, with a stress on the study of localizationphenomena. Therefore, this thesis highlights the emergence of localization in systemsdevoid of disorder due to an interference effect, the so-called Aharonov-Bohmcaging; as well as a geometrically disordered quantum Ising model displaying adynamics exploring a rich spectrum ranging from balistic diffusion to anomalousdiffusion, an then localization - this last example offers a scenario richer than theone exhibited by the dynamics of free particles in a disordered medium. Finally,we explored the possibility for Gaussian approaches to describe the dynamics ofinteracting systems and their relaxation toward thermal states
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Niset, Julien. "Quantum information with optical continuous variables: nonlocality, entanglement, and error correction". Doctoral thesis, Universite Libre de Bruxelles, 2008. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210459.

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L'objectif de ce travail de recherche est l'étude des posibilités offertes par une nouvelle approche de l'information quantique basée sur des variables quantiques continues. Lorsque ces variables continues sont portées par le champs éléctromagnétique, un grand nombre de protocoles d'information quantique peuvent être implémentés à l'aide de lasers et d'éléments d'optique linéaire standards. Cette simplicité expérimentale rend cette approche très intéressantes d'un point de vue pratique, en particulier pour le développement des futurs réseaux de communications quantiques.

Le travail peut se diviser en deux parties complémentaires. Dans la première partie, plus fondamentale, la relation complexe qui existe entre l'intrication et la nonlocalité de la mécanique quantique est étudiée sur base des variables optiques continues. Ces deux ressources étant essentielles pour l'information quantique, il est nécessaire de bien les comprendre et de bien les caractériser. Dans la seconde partie, orientée vers des applications concrètes, le problème de la correction d'erreur à variables continues est étudié. Pouvoir transmettre et manipuler l'information sans erreurs est nécessaire au bon développemnent de l'information quantique, mais, en pratique, les erreurs sont inévitables. Les codes correcteurs d'erreurs permettent de détecter et corriger ces erreures de manière efficace.


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Gondret, Victor. "On the entanglement of quasi-particles in a Bose-Einstein Condensate". Electronic Thesis or Diss., université Paris-Saclay, 2025. http://www.theses.fr/2025UPASP005.

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Ce mémoire de thèse traite de la non-séparabilité de paires de quasi-particules excitées par résonance paramétrique. Le dispositif expérimental utilisé pendant cette thèse permet de produire un condensat de Bose-Einstein d'hélium métastable. L'utilisation d'un gaz d'atomes ultra-froid permet d'atteindre des températures suffisamment basses afin de pouvoir observer des phénomènes intrinsèquement quantiques : la non-séparabilité de l'état. Dans ce travail, nous utilisons le condensat comme un réservoir cohérent permettant de peupler deux modes d'impulsions. L'avantage de l'hélium métastable est sa grande énergie interne, qui permet la détection électronique de particules uniques. Nous mesurons donc la position et le temps d'impact des particules après un temps de vol de 308 ms, ce qui permet de reconstruire la distribution en impulsion dans le piège. Dans la première contribution théorique de ce travail, nous démontrons que la mesure des fonctions de corrélation à deux et quatre corps permet de quantifier la non-séparabilité d'un état gaussien. Nous dérivons également un critère permettant d'attester la séparabilité de l'état via la seule mesure la fonction de corrélation à deux corps. Dans la partie expérimentale, nous améliorons la machine permettant de produire notre gaz ultra-froid, ainsi que sa stabilité. Par ailleurs, nous mettons en œuvre des techniques originales afin de dévier une partie des atomes et éviter la saturation de notre détecteur. Ces améliorations nous permettent ainsi d'observer la non-séparabilité de l'état
This thesis focuses on the non-separability of pairs of quasi-particles excited by parametric resonance. The experimental setup used here allows the production of a Bose-Einstein condensate of metastable helium. The use of an ultra-cold atomic gas makes it possible to reach sufficiently low temperatures to observe intrinsically quantum phenomena: the non-separability of the state. In this work, we use the condensate as a coherent reservoir to populate two momentum modes. The advantage of metastable helium is its high internal energy, which allows the electronic detection of single particles. We therefore measure the position and the time of impact of the particles after a time of flight of 308 ms, which allows us to reconstruct the in-trap momentum distribution. In the first theoretical contribution of this work, we demonstrate that measuring the two- and four-body correlation functions not only attests to, but also quantifies the non-separability of a Gaussian state. We also derive a new entanglement witness using only the two-body correlation function. In the experimental part, we improve the machine used to produce our ultra-cold gas and enhance its stability. We implement original techniques to deflect part of the atoms and avoid the saturation of our detector. These improvements allow us to observe the non-separability of the state
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Nocerino, Gaetano. "Gaussian and non-Gaussian resources in Quantum Information". Doctoral thesis, Universita degli studi di Salerno, 2013. http://hdl.handle.net/10556/994.

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2011 - 2012
This dissertation was carried out within the framework of the Quantum Information (QI). In particular, I have analyzed the main aspects: the protocol, the quantum states, the conditional measurements, and the decoherence. The protocol. I have studied the teleportation protocol, the entanglement swapping protocol, and the Bell’s inequality (which is the basis of some protocols such as the quantum cryptography). I have dealt with the maximization of the efficiency of each protocol, by acting on the generation of the appropriate quantum states. Starting from the known Squeezed Bell (SB) states that maximize the fidelity of teleportation, I have shown that even for the entanglement swapping protocol and for the violation of the Bell’s inequality, the SB states exhibit better performance than all the other continuous variable (CV) quantum states (for example squeezed vacuum states, subtracted photon squeezed states, added photon squeezed states, squeezed number states). Preparation of quantum states. I have presented an experimental scheme capable of generating, with good approximation, the SB states. I have identified a scheme that is based on conditional measures performed on ancillary quantum states. I have started to study an ideal scheme (free by inefficiencies and decoherence), obtaining the reproduction of the SB states. Then I have introduced the inefficiencies of detection, of the optical elements and of the conditional measurements. In the latter case, the scheme does not exactly reproduce the SB states, but tunable quantum states are obtained, which are very close to SB states. They exhibit a greater teleportation fidelity than all other realistic quantum states that we have analyzed. In addition, in collaboration with Prof. Salvatore Solimeno and Dr. Alberto Porzio of University of Naples "Federico II", I have studied (the work is still at a preliminary stage) the non-Gaussianity introduced by fluctuations in the pump amplitude of the Optical Parametric Oscillator(OPO) below threshold and with non-degenerate polarization. I have proved that such fluctuations lead to an increase of fidelity of teleportation with respect to the not fluctuating (and gaussian) case. Conditional Measurements. In the context of the QI, conditional measurements are used to prepare quantum states and to optimize the transfer of information, as required by the specific protocol. I propose a rather general formulation of the method of conditioning through ancillary measurements, in terms of the characteristic functions. I have considered the case of simultaneous measurements of single-photon, of homodyne detection, and of on/off type (via ideal and realistic POVM). Decoherence. The quantum properties are very sensitive to the interaction of the quantum systems with the external environment. For this reason, a part of this dissertation is devoted to analysis of the evolution of some quantum quantities under the action of the decoherence. In particular, I have studied how the effects of decoherence act on the following quantities: the purity, the quantum correlations, the content of information, the fidelity of teleportation of a coherent state, and the Bell’s inequality of a bi-partite Gaussian state that is transmitted through a realistic channel. I have added the experimental verification to the theoretical study, in collaboration with the University of Naples "Federico II" and under the guidance of Dr. Alberto Porzio and of Prof. Salvatore Solimeno. [edited by author]
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De, Fazio Cecilia. "Entanglement Entropy In Excited States". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/15833/.

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Negli ultimi anni l’entropia di entaglement è stata ampiamente studiata nel campo dell‘integrabilità. Con l‘introduzione del modello a replica è stato possibile portare alla luce le proprietà universali dell’ entropia di entanglement di un sistema bipartito nello stato di vuoto. In questa tesi si è investigato il problema dell’entropia di entanglement di un sistema bipartito in uno stato eccitato di singola particella. In particolare, si è considerata una teoria bosonica libera in un volume finito, in modo da sfruttare al meglio le tecniche dell‘integrabilità. Nel corso di questa analisi, è stato possibile rielaborare il modello a replica in un volume finito grazie ad un raddoppiamento della teoria bosonica che ha indotto una simmetria U(1) su ogni copia del modello. Tale tecnica, nota in letter- atura come doubling trick ha permesso di ricondurre il calcolo dell’entropia di Renyi a un’opportuna espansione in form factors dei campi U(1) implementanti tale simmetria e valutarne il contributo dominante nel limite in cui il volume è grande. I risultati ottenuti per la Second Rènyi entropy mostrano che in tale limite, l’eccesso di entanglement dovuto allo stato eccitato rispetto a quello di vuoto è indipendente dall’energia dello stato stesso e può essere interpretato come quantità che misura l’incertezza sulla localizzazione dell’eccitazione nelle due parti di cui è composto il sistema.
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Libros sobre el tema "Entanglement of Gaussian states"

1

Ferraro, Alessandro. Gaussian states in quantum information. Napoli: Bibliopolis, 2005.

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Lorch, Robert Stuart. State and local politics: The great entanglement. 3a ed. Englewood Cliffs, N.J: Prentice Hall, 1989.

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Lorch, Robert Stuart. State and local politics: The great entanglement. 4a ed. Englewood Cliffs, N.J: Prentice Hall, 1992.

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Lorch, Robert Stuart. State and local politics: The great entanglement. 5a ed. Englewood Cliffs, N.J: Prentice Hall, 1995.

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José, Carmelo, ed. Strongly correlated systems, coherence and entanglement. Singapore: World Scientific, 2007.

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Lorch, Robert Stuart. State and local politics: The great entanglement / Robert S. Lorch. 6a ed. Upper Saddle River, N.J: Prentice Hall, 2001.

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1964-, Buchleitner A., Viviescas C y Tiersch M, eds. Entanglement and decoherence: Foundations and modern trends. Berlin: Springer, 2009.

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1953-, Akulin V. M., ed. Decoherence, entanglement and information protection in complex quantum systems. Dordrecht: Springer, 2005.

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Paredes, Javier y G. G. Melies. Rudimentary Theory about Quantum Entanglement and Twin States: Rudimentary Theory about Quantum Entanglement and Twin States. Babelcube Inc, 2020.

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Annex. States of Entanglement: Data in the Irish Landscape. Actar D, 2021.

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Capítulos de libros sobre el tema "Entanglement of Gaussian states"

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Giedke, Géza, Lu-Ming Duan, J. Ignacio Cirac y Peter Zoller. "Distillability and Entanglement Purification for Gaussian States". En Quantum Information with Continuous Variables, 173–92. Dordrecht: Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-015-1258-9_15.

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Holevo, Alexander. "Gaussian states". En Probabilistic and Statistical Aspects of Quantum Theory, 187–218. Pisa: Edizioni della Normale, 2011. http://dx.doi.org/10.1007/978-88-7642-378-9_5.

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Rangamani, Mukund y Tadashi Takayanagi. "Entanglement in Excited States". En Holographic Entanglement Entropy, 125–43. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-52573-0_8.

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Gupta, Ved Prakash, Prabha Mandayam y V. S. Sunder. "Entanglement in Bipartite Quantum States". En The Functional Analysis of Quantum Information Theory, 39–62. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-16718-3_2.

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Schürmann, Michael. "Gaussian states on bialgebras". En Quantum Probability and Applications V, 347–67. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/bfb0085528.

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Wódkiewicz, Krzysztof y Berthold-Georg Englert. "Separability of Gaussian States". En Coherence and Quantum Optics VIII, 531–32. Boston, MA: Springer US, 2003. http://dx.doi.org/10.1007/978-1-4419-8907-9_153.

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Pato, Mauricio Porto. "Entanglement of Pseudo-Hermitian Random States". En Pseudo-Hermitian Random Matrices, 163–78. Cham: Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-60294-8_15.

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Simon, R. "Separability Criterion for Gaussian States". En Quantum Information with Continuous Variables, 155–72. Dordrecht: Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-015-1258-9_14.

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Chandra, N. y R. Ghosh. "Bipartite States of Photonic and Flying Electronic Qubits". En Quantum Entanglement in Electron Optics, 179–97. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-24070-6_8.

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Barron, Tatyana y Alexander Kazachek. "Entanglement of Mixed States in Kähler Quantization". En Springer Proceedings in Mathematics & Statistics, 381–85. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-4751-3_33.

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Actas de conferencias sobre el tema "Entanglement of Gaussian states"

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He, Wenhua, Christos N. Gagatsos, Dalziel J. Wilson y Saikat Guha. "Modal Entanglement Enhanced Deflectometry". En Quantum Sensing and Metrology, QTh1G.2. Washington, D.C.: Optica Publishing Group, 2024. https://doi.org/10.1364/qsm.2024.qth1g.2.

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We show that exciting a particular high-order spatial mode in a squeezed state affords increased sensitivity for probing a small surface tilt, over optimum classical illumination and Gaussian quantum illumination with a HG00beam.
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Danese, Dylan, Sabine Wollmann, Saroch Leedumrongwatthanakun, Will McCutcheon, Manuel Erhard, William N. Plick y Mehul Malik. "ℓ00ℓ entanglement and the twisted quantum eraser". En Quantum 2.0, QW3A.54. Washington, D.C.: Optica Publishing Group, 2024. http://dx.doi.org/10.1364/quantum.2024.qw3a.54.

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Demonstration of two-photon entanglement in the transverse Laguerre-Gaussian basis by performing a “twisted” quantum eraser. The state is generated using linear optics and measured using full state tomography with a fidelity up to 95.31%.
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Ma, Shan, Lihan Zhou, Junfeng Ma y Shibei Xue. "Bipartite entanglement of a bound entangled Gaussian state via a linear matrix inequality method*". En 2024 43rd Chinese Control Conference (CCC), 6777–82. IEEE, 2024. http://dx.doi.org/10.23919/ccc63176.2024.10661902.

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Zhu, Chenghong, Chengkai Zhu, Zhiping Liu y Xin Wang. "Entanglement cost of discriminating quantum states under locality constraints". En 2024 IEEE International Symposium on Information Theory (ISIT), 345–50. IEEE, 2024. http://dx.doi.org/10.1109/isit57864.2024.10619706.

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Torres, Juan Mauricio. "Quantum Operations Assisted by Multiphoton and Multiphonon States". En Latin America Optics and Photonics Conference, M3B.2. Washington, D.C.: Optica Publishing Group, 2024. https://doi.org/10.1364/laop.2024.m3b.2.

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Quantum operations in cavity-QED scenarios are theoretically investigated, where multiphoton states assist in generating atomic entanglement. Similar schemes are implementable with trapped ions. These operations can serve protocols such as entanglement purification.
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Haddad, Madlene, Offek Tziperman, Ron Ruimy y Ido Kaminer. "Electron-photon entanglement without recoil". En Quantum 2.0, QW3A.17. Washington, D.C.: Optica Publishing Group, 2024. http://dx.doi.org/10.1364/quantum.2024.qw3a.17.

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We present a novel entanglement type between free electrons and photons that requires no recoil, hidden within the multimode nature of electron radiation. This discovery opens new avenues for creating desired states of quantum light.
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Tziperman, Offek, Ron Ruimy, Alexey Gorlach y Ido Kaminer. "Creating Entanglement Through a Joint Decay Channel". En CLEO: Fundamental Science, FTu3O.4. Washington, D.C.: Optica Publishing Group, 2024. http://dx.doi.org/10.1364/cleo_fs.2024.ftu3o.4.

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We propose a protocol to create entanglement between emitters in cavity- or waveguide-QED through their decay to a common channel. Heralding on emitters’ states creates desired quantum light states such as cat and GKP.
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Gonzáldez-Arciniegas, Carlos, Olivier Pfister, Paulo Nussenzveig y Marcelo Martinelli. "Hidden Entanglement in Gaussian Cluster States". En Quantum 2.0. Washington, D.C.: OSA, 2020. http://dx.doi.org/10.1364/quantum.2020.qw6b.4.

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Law, C. K. y Phoenix S. Y. Poon. "Negativity of Gaussian states in noisy environment: Interpretations and Applications". En Workshop on Entanglement and Quantum Decoherence. Washington, D.C.: Optica Publishing Group, 2008. http://dx.doi.org/10.1364/weqd.2008.edd3.

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We reexamine the interpretation of negativity of a generally mixed two-mode Gaussian state by diagonalizing ρ TA (the partial transposition of density matrix ρ) directly. We show that negativity can be explicitly expressed in terms of an optimal uncertainty product corresponding to the greatest violation of a separability criterion based on positive partial transposition [1], In addition, the explicit form of the eigenvectors of ρ ta provides a way to construct entanglement witness operators [2]. We apply our analysis of negativity to disentanglement dynamics in two physical situations in optics. First, we study two-mode squeezed states interacting with symmetric linear baths. Second, we study the decoherence of hyper-entangled two-photon states due to polarization mode dispersion in optical fibers. In both problems, we present the time-dependence of negativity and indicate how the disentanglement times depend on system parameters.
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Lassen, Mikael, Ruifang Dong, Joel Heersink, Christoph Marquardt, Radim Filip, Gerd Leuchs, Ulrik L. Andersen y Alexander Lvovsky. "Continuous Variable Entanglement Distillation of Non-Gaussian States". En QUANTUM COMMUNICATION, MEASUREMENT AND COMPUTING (QCMC): Ninth International Conference on QCMC. AIP, 2009. http://dx.doi.org/10.1063/1.3131300.

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Informes sobre el tema "Entanglement of Gaussian states"

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Balachandran, A. P., L. Chandar y A. Momen. Edge states and entanglement entropy. Office of Scientific and Technical Information (OSTI), febrero de 1996. http://dx.doi.org/10.2172/212697.

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Friesen, Mark y Xuedong Hu. Exploiting Many-Body Bus States for Multi-Qubit Entanglement. Fort Belvoir, VA: Defense Technical Information Center, junio de 2013. http://dx.doi.org/10.21236/ada594989.

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Erästö, Tytti, Fei Su y Wilfred Wan. Navigating Security Dilemmas in Indo-Pacific Waters. Stockholm International Peace Research Institute, junio de 2024. http://dx.doi.org/10.55163/dkwb3559.

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This paper examines the drivers and implications of naval build-ups in the Indo-Pacific, considering key actors’ security objectives and threat perceptions, as well as the interplay of regional dynamics and strategic relations between nuclear-armed states. The focus is on undersea armament involving submarines and anti-submarine warfare (ASW) capabilities, which constitute a significant focus of military investments. The paper considers the related horizontal and vertical escalation risks, meaning a potential increase in the scope and scale of conflict. Particular attention is paid to nuclear-conventional entanglement related to the counterforce potential of ASW capabilities. In addition to seeking to raise awareness of these dynamics, the paper provides recommendations aimed at mitigating the risks related to the increased undersea activities in the Indo-Pacific.
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Bielinskyi, Andrii, Vladimir Soloviev, Serhiy Semerikov y Viktoria Solovieva. Detecting Stock Crashes Using Levy Distribution. [б. в.], agosto de 2019. http://dx.doi.org/10.31812/123456789/3210.

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In this paper we study the possibility of construction indicators-precursors relying on one of the most power-law tailed distributions – Levy’s stable distribution. Here, we apply Levy’s parameters for 29 stock indices for the period from 1 March 2000 to 28 March 2019 daily values and show their effectiveness as indicators of crisis states on the example of Dow Jones Industrial Average index for the period from 2 January 1920 to 2019. In spite of popularity of the Gaussian distribution in financial modeling, we demonstrated that Levy’s stable distribution is more suitable due to its theoretical reasons and analysis results. And finally, we conclude that stability α and skewness β parameters of Levy’s stable distribution which demonstrate characteristic behavior for crash and critical states, can serve as an indicator-precursors of unstable states.
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Bielinskyi, A., S. Semerikov, V. Solovieva y V. Soloviev. Levy distribution parameters as precursors of crisis phenomena. Видавничий будинок Мелітопольської міської друкарні, 2019. http://dx.doi.org/10.31812/123456789/3597.

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In spite of popularity of the Gaussian distribution in financial modeling, we demonstrated that Levy’s stable distribution is more suitable due to its theoretical reasons and analysis results. We study the possibility of construction indicators- precursors relying on one of the most power-law tailed distributions - Levy’s stable distribution. Here, we apply moving window based procedure for calculation of Levy’s parameters - a - stability and /?- skewness for daily values of Dow Jones Industrial Average (from 1 March 2000 to 28 March 2019), the gold price (from 1 April 1968 to 8 May 2019) and Brent crude oil price (from 2 January 1986 to 6 May 2019) which show their effectiveness as indicators of crisis states. For the construction of the indicators, were selected time series of and, accordingly, for oil. Dow Jones’ time series has the period from 2 January 1920 to 2019. We conclude that a and /3 parameters of Levy’s stable distribution of the observed assets, which demonstrate characteristic behavior for crash and critical states, can serve as an indicator-precursors of the unstable states.
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Bielinskyi, Andrii O., Serhii V. Hushko, Andriy V. Matviychuk, Oleksandr A. Serdyuk, Сергій Олексійович Семеріков, Володимир Миколайович Соловйов, Андрій Іванович Білінський, Андрій Вікторович Матвійчук y О. А. Сердюк. Irreversibility of financial time series: a case of crisis. Криворізький державний педагогічний університет, diciembre de 2021. http://dx.doi.org/10.31812/123456789/6975.

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The focus of this study to measure the varying irreversibility of stock markets. A fundamental idea of this study is that financial systems are complex and nonlinear systems that are presented to be non-Gaussian fractal and chaotic. Their complexity and different aspects of nonlinear properties, such as time irreversibility, vary over time and for a long-range of scales. Therefore, our work presents approaches to measure the complexity and irreversibility of the time series. To the presented methods we include Guzik’s index, Porta’s index, Costa’s index, based on complex networks measures, Multiscale time irreversibility index and based on permutation patterns measures. Our study presents that the corresponding measures can be used as indicators or indicator-precursors of crisis states in stock markets.
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Li, Baisong y Bo Xu. PR-469-19604-Z01 Auto Diagnostic Method Development for Ultrasonic Flow Meter. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), febrero de 2022. http://dx.doi.org/10.55274/r0012204.

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The objectives of this research are to develop methods for performing ultrasonic flow meter (USM) diagnostic evaluation automatically and a software tool with all necessary attachments. USM-based diagnostics have been established and thirteen categories of knowledge rules of existing cases have been learned and integrated. A search engine for relevant standards, specifications, and other documents of the measurement system has been developed, which enables the free search of text content. Further, with the assistance of modern reasoning techniques, the authorized user only needs to configure an EXCEL file or scripts to activate the rules of the knowledge base by using Drools technology. Therefore, the integration of any potential knowledge rules is convenient and requires no professional skills or changing of the internal source code of the software. Secondly, a new flow meter diagnostic method is proposed based on multiple information methodologies and it is based on the real-time measurement data, operation data, and video data if applicable. The method is intended to identify abnormal states of the measurement system on a real-time basis with the assistance of the knowledge rules and to provide a strategy for mitigating the meter error of components within the measurement system. Thirdly, the applications of Gaussian quadrature diagnostics in daily acquisition nomination change situations and compressor-induced pulsating flow scenarios have been investigated and results are shown in the document. Based on the results, it can be concluded that the measurement uncertainty caused by compressor-induced pulsating flows is obvious, while the measurement uncertainty caused by daily acquisition nomination change is relatively smaller. The software is then developed based on the knowledge, the idea of multiple information methods, and applications of the Gaussian quadrature diagnostics method with all necessary attachments. The architecture, the algorithm, and a few examples are introduced.
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Perdigão, Rui A. P. y Julia Hall. Empowering Next-Generation Synergies among Models and Data with Information Physical Quantum Technological Intelligence. Synergistic Manifolds, diciembre de 2024. https://doi.org/10.46337/241209.

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We present and deploy our methodological and technological framework of Information Physical Quantum Technological Intelligence (IPQuTI), to empower next-generation mathematically robust, physically consistent, computationally efficient and operationally scalable synergies among models and data across multisectoral theoretical and applied workflows. Going beyond digital computing platforms, IPQuTI encompasses a richer basis alphabet of fundamental quantum states (information building blocks) and a high-order set of superposition and entanglement functionals (grammar) beyond the state of the art in quantum information itself. These are foundational core underneath our increased ability to encode, analyze, generate and simulate a broader physical language: one that is able to seamlessly treat complex high-dimensional data and model structures, interactions and operations with faster computational speed, higher robustness, physical consistency, information fidelity, spatiotemporal resolution and lead. For example, in the setting of ensemble operations, IPQuTI encapsulates an entire spatiotemporal system of events into a block operation as a coherent universe. Turning lengthy intense computational churning of approximate equations and massive datasets into a post-quantum spatiotemporal pulse of rich spatiotemporal diversity, spanning deterministic and stochastic synergies among models and data into a unified solution. With nonlinear geophysical applications in mind, IPQuTI is explored in key contexts of Data Assimilation, Data Fusion, Machine Learning, Predictability Investigation and Uncertainty Quantification. Firstly, to further optimize gold-standard state-of-art (SoA) solutions, providing them with a new efficient and robust platform to operate. Second, to overcome known SoA challenges, thereby contributing towards their methodological and practical upgrade. Third, to unveil novel features adding methodological and applied value to these areas, including handling sparse records, perturbations and extremes.
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