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Journal articles on the topic 'Quantum double model'

Author: Grafiati

Published: 7 December 2024

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1

Favalli, T., and A. Smerzi. "A model of quantum spacetime." AVS Quantum Science 4, no. 4 (December 2022): 044403. http://dx.doi.org/10.1116/5.0107210.

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We consider a global quantum system (the “Universe”) satisfying a double constraint, both on total energy and total momentum. Generalizing the Page and Wootters quantum clock formalism, we provide a model of 3 + 1 dimensional, non-relativistic, quantum spacetime emerging from entanglement among different subsystems in a globally “timeless” and “positionless” Universe.

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2

Fiedler, Leander, and Pieter Naaijkens. "Haag duality for Kitaev’s quantum double model for abelian groups." Reviews in Mathematical Physics 27, no. 09 (October 2015): 1550021. http://dx.doi.org/10.1142/s0129055x1550021x.

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We prove Haag duality for cone-like regions in the ground state representation corresponding to the translational invariant ground state of Kitaev’s quantum double model for finite abelian groups. This property says that if an observable commutes with all observables localized outside the cone region, it actually is an element of the von Neumann algebra generated by the local observables inside the cone. This strengthens locality, which says that observables localized in disjoint regions commute. As an application, we consider the superselection structure of the quantum double model for abelian groups on an infinite lattice in the spirit of the Doplicher–Haag–Roberts program in algebraic quantum field theory. We find that, as is the case for the toric code model on an infinite lattice, the superselection structure is given by the category of irreducible representations of the quantum double.

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3

Chen, Lei, Zhen-Yu Wang, Wu Hui, Cheng-Yu Chu, Ji-Min Chai, Jin Xiao, Yu Zhao, and Jin-Xiang Ma. "Quantum ratchet effect in a time non-uniform double-kicked model." International Journal of Modern Physics B 31, no. 16-19 (July 26, 2017): 1744063. http://dx.doi.org/10.1142/s0217979217440635.

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The quantum ratchet effect means that the directed transport emerges in a quantum system without a net force. The delta-kicked model is a quantum Hamiltonian model for the quantum ratchet effect. This paper investigates the quantum ratchet effect based on a time non-uniform double-kicked model, in which two flashing potentials alternately act on a particle with a homogeneous initial state of zero momentum, while the intervals between adjacent actions are not equal. The evolution equation of the state of the particle is derived from its Schrödinger equation, and the numerical method to solve the evolution equation is pointed out. The results show that quantum resonances can induce the ratchet effect in this time non-uniform double-kicked model under certain conditions; some quantum resonances, which cannot induce the ratchet effect in previous models, can induce the ratchet effect in this model, and the strengths of the ratchet effect in this model are stronger than those in previous models under certain conditions. These results enrich people’s understanding of the delta-kicked model, and provides a new optional scheme to control the quantum transport of cold atoms in experiment.

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Cui, Shawn X., Dawei Ding, Xizhi Han, Geoffrey Penington, Daniel Ranard, Brandon C. Rayhaun, and Zhou Shangnan. "Kitaev's quantum double model as an error correcting code." Quantum 4 (September 24, 2020): 331. http://dx.doi.org/10.22331/q-2020-09-24-331.

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Kitaev's quantum double models in 2D provide some of the most commonly studied examples of topological quantum order. In particular, the ground space is thought to yield a quantum error-correcting code. We offer an explicit proof that this is the case for arbitrary finite groups. Actually a stronger claim is shown: any two states with zero energy density in some contractible region must have the same reduced state in that region. Alternatively, the local properties of a gauge-invariant state are fully determined by specifying that its holonomies in the region are trivial. We contrast this result with the fact that local properties of gauge-invariant states are not generally determined by specifying all of their non-Abelian fluxes --- that is, the Wilson loops of lattice gauge theory do not form a complete commuting set of observables. We also note that the methods developed by P. Naaijkens (PhD thesis, 2012) under a different context can be adapted to provide another proof of the error correcting property of Kitaev's model. Finally, we compute the topological entanglement entropy in Kitaev's model, and show, contrary to previous claims in the literature, that it does not depend on whether the ``log dim R'' term is included in the definition of entanglement entropy.

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Vimala, Palanichamy, and N. R. Nithin Kumar. "Explicit Quantum Drain Current Model for Symmetric Double Gate MOSFETs." Journal of Nano Research 61 (February 2020): 88–96. http://dx.doi.org/10.4028/www.scientific.net/jnanor.61.88.

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In this article, an analytical model for Double gate Metal Oxide Semiconductor Field Effect Transistor (DG MOSFET) is developed including Quantum effects. The Schrodinger–Poisson’s equation is used to develop the analytical Quantum model using Variational method. A mathematical expression for inversion charge density is obtained and the model was developed with quantum effects by means of oxide capacitance for different channel thickness and gate oxide thickness. Based on inversion charge density model the compact model is developed for transfer characteristics, transconductance and C-V curves of DG MOSFETs. The results of the model are compared to the simulated results. The comparison shows the accuracy of the proposed model.

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Duan, Zhongzheng, Wenxi Luo, and Xiaohan Xu. "Transmission coefficient in double barrier quantum tunnelling effect." Theoretical and Natural Science 25, no. 1 (December 20, 2023): 199–204. http://dx.doi.org/10.54254/2753-8818/25/20240965.

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At the turn of the twentieth century, the establishment of quantum theory propelled rapid advancements, particularly in the understanding of quantum tunnellinga fundamental phenomenon in quantum mechanics crucial for various physical processes. The quantum phenomenon of particle passes through potential barriers is of great importance. In classical physics, when the energy of a particle is less than the height of a double barrier structure, it is impossible for it to pass through. However, quantum mechanics allows a particle to penetrate the barrier and emerge on the other side. This paper explores the quantum tunnelling effect, focusing on the single potential barrier model in one dimension and subsequently extending to the double potential barrier model. The Schrdinger equation provides the foundational framework for elucidating the motion of microscopic particles, emphasizing wave-particle duality inherent in quantum mechanics. The analysis of the single potential barrier model involves solving the Schrdinger equation in different regions, determining wave functions and coefficients through boundary conditions. The transmission coefficient is derived, representing the probability of a particle passing through a barrier. In the case of a thick barrier, an approximate form for transmission coefficient is provided, demonstrating the exponential decrease in transmission probability with increasing barrier thickness.

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7

Chen, Zuo Peng, and Jin Ran Gao. "The Research of Qubit-Field System Quantum Entanglement under J-C Model." Applied Mechanics and Materials 203 (October 2012): 464–68. http://dx.doi.org/10.4028/www.scientific.net/amm.203.464.

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In this article we plan to get a equation about the concurrence. We select the J-C model, then introduce the double-cavity and double-atom system in this model, and consider the two-atom entanglement. By using the Taylor expansion to calculate the quantum correlations concurrence in this system. Finally we deduce this equation which can predict the sudden death and rebirth of the spin quantum entanglement.

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8

Edwards, D. M., A. C. M. Green, and K. Kubo. "Quantum spins in the double exchange model of manganites." Physica B: Condensed Matter 259-261 (January 1999): 810–11. http://dx.doi.org/10.1016/s0921-4526(98)00944-2.

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9

Beigi, Salman, Peter W. Shor, and Daniel Whalen. "The Quantum Double Model with Boundary: Condensations and Symmetries." Communications in Mathematical Physics 306, no. 3 (June 28, 2011): 663–94. http://dx.doi.org/10.1007/s00220-011-1294-x.

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10

de Martino, Salvatore, Silvio de Siena, and Pasquale Sodano. "Critical behavior of the quantum double-sine-Gordon model." Physical Review B 32, no. 5 (September 1, 1985): 3304–5. http://dx.doi.org/10.1103/physrevb.32.3304.

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11

Cowtan, Alexander, and Shahn Majid. "Quantum double aspects of surface code models." Journal of Mathematical Physics 63, no. 4 (April 1, 2022): 042202. http://dx.doi.org/10.1063/5.0063768.

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We revisit the Kitaev model for fault tolerant quantum computing on a square lattice with underlying quantum double D( G) symmetry, where G is a finite group. We provide projection operators for its quasiparticles content as irreducible representations of D( G) and combine this with D( G)-bimodule properties of open ribbon excitation spaces [Formula: see text] to show how open ribbons can be used to teleport information between their endpoints s0, s1. We give a self-contained account that builds on earlier work but emphasizes applications to quantum computing as surface code theory, including gates on D( S3). We show how the theory reduces to a simpler theory for toric codes in the case of [Formula: see text], including toric ribbon operators and their braiding. In the other direction, we show how our constructions generalize to D( H) models based on a finite-dimensional Hopf algebra H, including site actions of D( H) and partial results on ribbon equivariance even when the Hopf algebra is not semisimple.

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12

HASEGAWA, MASAHITO. "A quantum double construction in Rel." Mathematical Structures in Computer Science 22, no. 4 (May 18, 2012): 618–50. http://dx.doi.org/10.1017/s0960129511000703.

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We study bialgebras and Hopf algebras in the compact closed categoryRelof sets and binary relations. Various monoidal categories with extra structure arise as the categories of (co)modules of bialgebras and Hopf algebras inRel. In particular, for any groupG, we derive a ribbon category of crossedG-sets as the category of modules of a Hopf algebra inRelthat is obtained by the quantum double construction. This category of crossedG-sets serves as a model of the braided variant of propositional linear logic.

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13

Secchi, Andrea, and Filippo Troiani. "Multi-Dimensional Quantum Capacitance of the Two-Site Hubbard Model: The Role of Tunable Interdot Tunneling." Entropy 25, no. 1 (December 31, 2022): 82. http://dx.doi.org/10.3390/e25010082.

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Few-electron states confined in quantum-dot arrays are key objects in quantum computing. The discrimination between these states is essential for the readout of a (multi-)qubit state, and can be achieved through a measurement of the quantum capacitance within the gate-reflectometry approach. For a system controlled by several gates, the dependence of the measured capacitance on the direction of the oscillations in the voltage space is captured by the quantum capacitance matrix. Herein, we apply this tool to study a double quantum dot coupled to three gates, which enable the tuning of both the bias and the tunneling between the two dots. Analytical solutions for the two-electron case are derived within a Hubbard model, showing the overall dependence of the quantum capacitance matrix on the applied gate voltages. In particular, we investigate the role of the tunneling gate and reveal the possibility of exploiting interdot coherences in addition to charge displacements between the dots. Our results can be directly applied to double-dot experimental setups, and pave the way for further applications to larger arrays of quantum dots.

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14

Strubbe, Filip. "Single-Photon Double-Slit Interference in the 4+1 Formalism." Universe 8, no. 10 (September 29, 2022): 511. http://dx.doi.org/10.3390/universe8100511.

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Unifying quantum theory with general relativity is challenging because of several problems related to time and to collapse in quantum measurements. In the double-slit experiment, the questions are how the momentum of the photon is transferred to a specific location on the screen and how the double slit recoils accordingly. This work investigates if these problems can be solved by adding a second time τ, which acts as an external evolution parameter, to standard four-dimensional spacetime. Within the resulting 4+1 formalism, a model for the single-photon double-slit experiment is developed. On the one hand, each spacetime associated to a value of τ relies on classical worldlines that obey local momentum conservation. On the other hand, these worldlines are allowed to readjust as a function of τ such that the quantum phenomenon of double-slit interference can be reproduced. The model explains how determinate outcomes are produced and how momentum transfer occurs in a way that satisfies the principles of relativity and local momentum conservation. As a result, the measurement problem and the problem of time evaporate, and an explanation for our experience of the present emerges. Since the presented model succeeds in explaining a key quantum phenomenon with essentially classical worldlines, this is relevant for the field of quantum gravity.

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15

Wang, M. J., F. Y. Yue, and F. M. Guo. "Photoelectric Characteristics of Double Barrier Quantum Dots-Quantum Well Photodetector." Advances in Condensed Matter Physics 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/920805.

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The photodetector based on double barrier AlAs/GaAs/AlAs heterostructures and a layer self-assembled InAs quantum dots and In0.15Ga0.85As quantum well (QW) hybrid structure is demonstrated. The detection sensitivity and detection ability under weak illuminations have been proved. The dark current of the device can remain at 0.1 pA at 100 K, even lower to3.05×10-15 A, at bias of −1.35 V. Its current responsivity can reach about6.8×105 A/W when 1 pw 633 nm light power and −4 V bias are added. Meanwhile a peculiar amplitude quantum oscillation characteristic is observed in testing. A simple model is used to qualitatively describe. The results demonstrate that the InAs monolayer can effectively absorb photons and the double barrier hybrid structure with quantum dots in well can be used for low-light-level detection.

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16

Bagrov, V. G., D. M. Gitman, A. D. Levin, and M. S. Meireles. "Entanglement of two-electron spin states in a double quantum dot." International Journal of Quantum Information 15, no. 01 (February 2017): 1750006. http://dx.doi.org/10.1142/s021974991750006x.

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Recently, an implementation of a universal set of one- and two-quantum-bit gates for quantum computation using spin states of coupled single-electron quantum dots was proposed. It was demonstrated that it is possible to execute a coherent control of a quantum system based on two-electron spin states in a double quantum dot, allowing state preparation, coherent manipulation, and projective readout. This possibility is based on rapid electrical control of the spin exchange interaction. These results motivated us to develop a formal theoretical study of the corresponding model of two coupled spins placed in a magnetic field and subjected to a time-dependent mutual Heisenberg interaction. Using possible exact solutions of the corresponding quantum problem, we study entangling of different separable initial states in this model. It is demonstrated that the entanglement due to a time-dependent Heisenberg interaction is dominating in comparison with the entanglement due to the action of an external magnetic field.

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Cheon, Taksu, and Sergey S. Poghosyan. "Asymmetric Quantum Transport in a Double-Stranded Kronig–Penney Model." Journal of the Physical Society of Japan 84, no. 6 (June 15, 2015): 064006. http://dx.doi.org/10.7566/jpsj.84.064006.

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18

Chaves, Ferney, David Jiménez, and Jordi Suñé. "Explicit quantum potential and charge model for double-gate MOSFETs." Solid-State Electronics 54, no. 5 (May 2010): 530–35. http://dx.doi.org/10.1016/j.sse.2010.01.015.

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19

Halley, J. W., and David Price. "Quantum theory of the double layer: Model including solvent structure." Physical Review B 35, no. 17 (June 15, 1987): 9095–102. http://dx.doi.org/10.1103/physrevb.35.9095.

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20

Penzin, Oleg, Gernot Paasch, and Lee Smith. "Nonparabolic Multivalley Quantum Correction Model for InGaAs Double-Gate Structures." IEEE Transactions on Electron Devices 60, no. 7 (July 2013): 2246–50. http://dx.doi.org/10.1109/ted.2013.2264165.

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21

Cruz-León, Sergio, Alvaro Vázquez-Mayagoitia, Simone Melchionna, Nadine Schwierz, and Maria Fyta. "Coarse-Grained Double-Stranded RNA Model from Quantum-Mechanical Calculations." Journal of Physical Chemistry B 122, no. 32 (July 25, 2018): 7915–28. http://dx.doi.org/10.1021/acs.jpcb.8b03566.

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22

Sacchetti, Andrea. "Quantum resonances and time decay for a double-barrier model." Journal of Physics A: Mathematical and Theoretical 49, no. 17 (March 18, 2016): 175301. http://dx.doi.org/10.1088/1751-8113/49/17/175301.

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23

DEKKER, H. "THE DISSIPATIVE DOUBLE-WELL POTENTIAL: A MULTILEVEL SPIN HOPPING ANALYSIS." Modern Physics Letters B 05, no. 05 (February 28, 1991): 351–56. http://dx.doi.org/10.1142/s0217984991000411.

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A novel treatment is presented of the real-time dynamics of a quantum mechanical particle in a dissipative double-well potential at finite temperatures. The analysis is based on the bilinear coupling model Hamiltonian à la Zwanzig. The energy spectrum consists of a ladder of vibrational doublets. The usual truncation to the ground state doublet — à la Leggett et al. — is not required. The intra-doublet spin-boson dynamics is evaluated in the “noninteracting-blip approximation”. The inter-doublet vibrational relaxation gives rise to a stochastic hopping process.

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24

Liu, Yu-Jie, Jing-Jing Wang, Li Zheng, Ying Shi, and Li Xiong. "Dynamic behavior of the quantum correlations of two cavity fields in the double Jaynes–Cummings model." Laser Physics Letters 19, no. 4 (March 4, 2022): 045204. http://dx.doi.org/10.1088/1612-202x/ac5521.

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Abstract The influence of the atom’s spatial degrees of freedom and the purity of the initial state on the dynamics of Bell non-locality, entanglement, geometric measure of quantum discord (GMQD) and quantum discord in a double Jaynes–Cummings model are investigated. We study the above four quantum correlations for an initial Werner-like state between the electronic states of the two atoms and between the two cavities respectively and find that all these quantum correlations are sensitive to the wave packet width and the purity of the initial state. For Bell non-locality, we find the phenomenon of sudden death and sudden birth, whereas the other three quantum correlations decay to zero asymptotically. We find that both the wave packet width and the purity of the initial state affect the GMQD and quantum discord in a similar way and we also notice that GMQD and quantum discord always exist, except where the purity of the initial state is zero, while Bell non-locality and entanglement can occur only when the purity meets certain conditions.

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25

Kasapoglu, Esin, Melike Behiye Yücel, and Carlos A. Duque. "Harmonic-Gaussian Symmetric and Asymmetric Double Quantum Wells: Magnetic Field Effects." Nanomaterials 13, no. 5 (February 27, 2023): 892. http://dx.doi.org/10.3390/nano13050892.

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In this study, we considered the linear and non-linear optical properties of an electron in both symmetrical and asymmetrical double quantum wells, which consist of the sum of an internal Gaussian barrier and a harmonic potential under an applied magnetic field. Calculations are in the effective mass and parabolic band approximations. We have used the diagonalization method to find eigenvalues and eigenfunctions of the electron confined within the symmetric and asymmetric double well formed by the sum of a parabolic and Gaussian potential. A two-level approach is used in the density matrix expansion to calculate the linear and third-order non-linear optical absorption and refractive index coefficients. The potential model proposed in this study is useful for simulating and manipulating the optical and electronic properties of symmetric and asymmetric double quantum heterostructures, such as double quantum wells and double quantum dots, with controllable coupling and subjected to externally applied magnetic fields.

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26

MCMAHON, W. E., T. MILLER, and T. C. CHIANG. "A THEORETICAL AND EXPERIMENTAL STUDY OF ELECTRONIC CONFINEMENT, COUPLING, AND TRANSLAYER INTERACTION IN NOBLE-METAL QUANTUM-WELL STRUCTURES." Modern Physics Letters B 08, no. 18 (August 10, 1994): 1075–96. http://dx.doi.org/10.1142/s0217984994001084.

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Noble-metal multilayer systems have been grown and examined with angle-resolved photoemission. Surface states, and single and double quantum wells have been studied experimentally; the results can be explained with a simple theoretical model based upon Bloch electrons. In this paper, we will present our model and then give a description of some experimental studies which utilize the model. In particular, we will consider double-quantum-well systems which can be used to examine basic aspects of electronic confinement, layer–layer coupling, and translayer interaction through a barrier.

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DEBALD, STEFAN, TOBIAS BRANDES, and BERNHARD KRAMER. "NONLINEAR ELECTRON TRANSPORT THROUGH DOUBLE QUANTUM DOTS COUPLED TO CONFINED PHONONS." International Journal of Modern Physics B 17, no. 28 (November 10, 2003): 5471–75. http://dx.doi.org/10.1142/s0217979203020594.

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The non-linear electron current through a double quantum dot embedded in a free standing quantum well is investigated. In such a model for a nano-size phonon cavity, the transport at low temperatures is mediated by the spontaneous emission of acoustic phonons. Phonon quantum size effects can be detected as steps in the current. Moreover, for our model we find van-Hove singularities in the phonon density of states that give rise to a strong, tuneable increase of phonon emission into characteristic modes. The emission characteristic, depending on the position of the dots in the cavity, is also considered.

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Gentile, F., A. Montorsi, and M. Roncaglia. "Entanglement generation and dynamics for a Bose–Hubbard model in a double-well potential." International Journal of Quantum Information 12, no. 07n08 (November 2014): 1560014. http://dx.doi.org/10.1142/s021974991560014x.

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The study of entanglement between bosonic systems is of primary importance for establishing feasible resources needed for implementing quantum information protocols, both in their interacting atomic or photonic realizations. Atomic systems are particularly efficient in the production of large amounts of entanglement, providing higher information density than conventional qubit entangled states. Such increased quantum resources pave the way to novel fundamental tests of nature and efficient applications in quantum information, metrology and sensing. We consider a basic setup made up of two parties A and B, each one populated by a single level bosonic variable. The bosons are interacting and can hop between A and B, thus describing a two-site Bose–Hubbard Hamiltonian. We consider the generation of quantum states in several situations that cover the majority of physical realizations: ground state, finite temperature, unitary dynamics, dissipation through dephasing and loss of particles. The system is analyzed through truncated exact diagonalization, as a function of the microscopic parameters. The nonseparability of the obtained quantum states is estimated by means of the negativity, which has recently been proven to be a suitable measure of entanglement [M. Roncaglia, A. Montorsi and M. Genovese, Phys. Rev. A 90 (2014) 062303]. Finally, we calculate lower bounds of the entanglement of formation (EOF), an indicator that quantifies the minimal amount of entanglement resources needed to build up such states.

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Li, Qiao, Bin Cheng, Moyu Chen, Bo Xie, Yongqin Xie, Pengfei Wang, Fanqiang Chen, et al. "Tunable quantum criticalities in an isospin extended Hubbard model simulator." Nature 609, no. 7927 (September 14, 2022): 479–84. http://dx.doi.org/10.1038/s41586-022-05106-0.

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AbstractStudying strong electron correlations has been an essential driving force for pushing the frontiers of condensed matter physics. In particular, in the vicinity of correlation-driven quantum phase transitions (QPTs), quantum critical fluctuations of multiple degrees of freedom facilitate exotic many-body states and quantum critical behaviours beyond Landau’s framework1. Recently, moiré heterostructures of van der Waals materials have been demonstrated as highly tunable quantum platforms for exploring fascinating, strongly correlated quantum physics2–22. Here we report the observation of tunable quantum criticalities in an experimental simulator of the extended Hubbard model with spin–valley isospins arising in chiral-stacked twisted double bilayer graphene (cTDBG). Scaling analysis shows a quantum two-stage criticality manifesting two distinct quantum critical points as the generalized Wigner crystal transits to a Fermi liquid by varying the displacement field, suggesting the emergence of a critical intermediate phase. The quantum two-stage criticality evolves into a quantum pseudo criticality as a high parallel magnetic field is applied. In such a pseudo criticality, we find that the quantum critical scaling is only valid above a critical temperature, indicating a weak first-order QPT therein. Our results demonstrate a highly tunable solid-state simulator with intricate interplay of multiple degrees of freedom for exploring exotic quantum critical states and behaviours.

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Xiang, Hao. "The improved quantum genetic algorithm with its application in fault diagnosis." Journal of Physics: Conference Series 2640, no. 1 (November 1, 2023): 012002. http://dx.doi.org/10.1088/1742-6596/2640/1/012002.

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Abstract In this paper, by analyzing the characteristics of the simulated annealing algorithm (SA) and the real double-chain coding target gradient quantum genetic algorithm (DCQGA), the real double-chain coding target gradient quantum genetic simulated annealing algorithm (DCQGSAA) is proposed. Because the performance of LSSVR is extraordinarily sensitive to its key parameters, the proposed algorithm is used to optimize these parameters, then a hybrid non-parametric prediction model is put forward. This model is used in fault prediction of liquid rocket engine thrust. The simulation results show that the proposed model is effective for small samples and multi-dimensional fault prediction.

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AOKI, KEN-ICHI, and TAMAO KOBAYASHI. "PHASE TRANSITION OF THE DISSIPATIVE DOUBLE-WELL QUANTUM MECHANICS." Modern Physics Letters B 26, no. 30 (October 22, 2012): 1250202. http://dx.doi.org/10.1142/s0217984912502028.

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We investigate the critical dissipation of the double-well quantum mechanics. We adopt two-state approximation to define effective Ising models and apply the block decimation renormalization group and the finite range scaling method recently proposed for the long range Ising model. We briefly report the numerical results of the critical dissipation for various model parameters.

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Herrebrugh, Albert V. ‎. "Determinism In Quantum Slit-Experiments." Hyperscience International Journals 2, no. 3 (September 2022): 115–21. http://dx.doi.org/10.55672/hij2022pp115-121.

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A mathematical model for the slit experiments in the heart of quantum mechanics is developed to gain insight into quantum ‎theory. The proposed system-theoretical model is entirely based on commutative mathematics, i.e. convolution, and integral ‎transformations, and starts with spacetime functions with inherent energy-based cause and effect relations of the state-‎function Ѱ in the complex Hilbert space. The benefits of his approach are as 1-Invariance in time reversal. 2-Deterministic ‎result functions in the model in line with the outcome of slit experiments. 3- Separation of causality and cross-correlations of ‎attained states. 4- Disappearance of a posteriori probability of quantum states. 5- Quantum a priori fixed states after ‎causality interactions have ended, (even) when quanta are (light-years) separated. The model predicts the patterns in the ‎experiments with mathematical functions of the energy distributions. The quantum mechanical counterpart description of the ‎physical reality of slit experiments thus may be considered complete in A. Einstein’s definition. The patterns in double slit ‎experiments are found to be an effect of energy (amplitude-) modulation. An equivalent double-slit pattern can be retrieved ‎from an input modulated 1-slit experiment excluding interference interpretations. The system-theoretical model uses generic ‎properties of quanta and evolves into determinism in ‎quantum mechanics slit experiments. The mathematics in the model ‎handles beables by treatment ‎of momentum p in system theoretical I/O relations of the transformed functions and allows the ‎proposed description by the avoidance of a direct addressing of the individual quanta through variables. The following ‎method yields exact, non-probabilistic results.‎

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Garashchuk, Sophya, Bing Gu, and James Mazzuca. "Calculation of the Quantum-Mechanical Tunneling in Bound Potentials." Journal of Theoretical Chemistry 2014 (April 24, 2014): 1–11. http://dx.doi.org/10.1155/2014/240491.

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The quantum-mechanical tunneling is often important in low-energy reactions, which involve motion of light nuclei, occurring in condensed phase. The potential energy profile for such processes is typically represented as a double-well potential along the reaction coordinate. In a potential of this type defining reaction probabilities, rigorously formulated only for unbound potentials in terms of the scattering states with incoming/outgoing scattering boundary conditions, becomes ambiguous. Based on the analysis of a rectangular double-well potential, a modified expression for the reaction probabilities and rate constants suitable for arbitrary double- (or multiple-) well potentials is developed with the goal of quantifying tunneling. The proposed definition involves energy eigenstates of the bound potential and exact quantum-mechanical transmission probability through the barrier region of the corresponding scattering potential. Applications are given for several model systems, including proton transfer in a HO–H–CH3 model, and the differences between the quantum-mechanical and quasiclassical tunneling probabilities are examined.

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Xu, Qing-Jun, and Shi-Ying Zhang. "The Dynamics of Quantum Entanglement and General Quantum Correlations in the Double Tavis-Cumming Model." International Journal of Theoretical Physics 55, no. 3 (September 9, 2015): 1438–46. http://dx.doi.org/10.1007/s10773-015-2783-z.

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Zhu, D., S. Johri, N. M. Linke, K. A. Landsman, C. Huerta Alderete, N. H. Nguyen, A. Y. Matsuura, T. H. Hsieh, and C. Monroe. "Generation of thermofield double states and critical ground states with a quantum computer." Proceedings of the National Academy of Sciences 117, no. 41 (September 28, 2020): 25402–6. http://dx.doi.org/10.1073/pnas.2006337117.

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Finite-temperature phases of many-body quantum systems are fundamental to phenomena ranging from condensed-matter physics to cosmology, yet they are generally difficult to simulate. Using an ion trap quantum computer and protocols motivated by the quantum approximate optimization algorithm (QAOA), we generate nontrivial thermal quantum states of the transverse-field Ising model (TFIM) by preparing thermofield double states at a variety of temperatures. We also prepare the critical state of the TFIM at zero temperature using quantum–classical hybrid optimization. The entanglement structure of thermofield double and critical states plays a key role in the study of black holes, and our work simulates such nontrivial structures on a quantum computer. Moreover, we find that the variational quantum circuits exhibit noise thresholds above which the lowest-depth QAOA circuits provide the best results.

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36

Al-Nashy, Baqer, Sabeah Jasim, Ali Gehad Al-Shatravi, and Amin H. Al-Khursan. "Spontaneously generated coherence in ladder-plus-Y double quantum dot system." Proceedings of the Institution of Mechanical Engineers, Part N: Journal of Nanomaterials, Nanoengineering and Nanosystems 233, no. 2-4 (June 2019): 65–71. http://dx.doi.org/10.1177/2397791419859159.

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A model was presented for linear susceptibility in ladder-plus-Y configuration of double quantum dot system using density matrix theory and including spontaneously generated coherence of Λ-type system. Wetting layer and quantum dot inhomogeneity were considered in the calculations, which gives a practical description of double quantum dot structures well. With increasing spontaneously generated coherence from Λ-component, the dispersion was increased and shifted under spontaneously generated coherence. The inclusion of wetting layer under spontaneously generated coherence increases gain which coincides with the published results. A possibility of slow light was predicted.

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37

Guarini, Eleonora, Douglas D. DiJulio, José I. Marquez Damian, Ubaldo Bafile, and Milva Celli. "Hydrogen Deuteride for Cold Neutron Production: A Model for the Double Differential Cross Section." Applied Sciences 14, no. 11 (May 30, 2024): 4718. http://dx.doi.org/10.3390/app14114718.

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The present work deals with the modeling of the response to neutrons of heteronuclear diatomic liquids, with special interest in the case of hydrogen deuteride (HD), as a possible candidate for the moderation process required in the production of cold neutrons. Preliminary evaluations of the model giving the neutron double differential cross section of a heteronuclear vibrating rotor were performed in the recent past by using, as a first approximation, the ideal gas law for the center-of-mass translational dynamics. Here, the state-of-the-art methodology (based on the use of quantum simulations of the velocity autocorrelation function) for predicting the neutron response of moderately quantum fluids (like molecular hydrogen and deuterium at low temperatures) is applied to the heteronuclear form of this molecular liquid. The unavailability of the double differential cross section experimental data on liquid HD still compels us to test the calculations only at an integral level, i.e., against the only available measurements of the total neutron cross section of HD. Despite the well-tested and parameter-free computational approach, which includes proper consideration of the quantum effects, the present findings on HD indicate the evident need for more accurate measurements of its total cross section in extended ranges of incident energy, as well as of an experimental determination of the double differential cross section of this mild quantum liquid. For further applicative purposes, a very useful by-product of this study is the determination of the self diffusion coefficient D of the HD in the liquid phase.

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38

Kisin, Mikhail V., Mitra Dutta, and Michael A. Stroscio. "ELECTRON-PHONON INTERACTIONS IN INTERSUBBAND LASER HETEROSTRUCTURES." International Journal of High Speed Electronics and Systems 12, no. 04 (December 2002): 939–68. http://dx.doi.org/10.1142/s0129156402001873.

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We present a simple semianalytical model, which allows comprehensive analysis of the LO-phonon assisted electron relaxation in quantum well intersubband semiconductor lasers. Examples of scattering rate tailoring in type-I double quantum well heterostructures and analysis of the subband depopulation process in type-II heterostructures illustrate applicability of the model.

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Ferraro, Dario, Michele Campisi, Gian Marcello Andolina, Vittorio Pellegrini, and Marco Polini. "Quantum resources for energy storage." EPJ Web of Conferences 230 (2020): 00003. http://dx.doi.org/10.1051/epjconf/202023000003.

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Recently the possibility to exploit quantum-mechanical effects to increase the performance of energy storage has raised a great interest. It consists of N two-level systems coupled to a single photonic mode in a cavity. We demonstrate the emergence of a quantum advantage in the charging power on this collective model (Dicke Quantum Battery) with respect to the one in which each two-level system is coupled to its own separate cavity mode (Rabi Quantum Battery). Moreover, we discuss the model of a Quantum Supercapacitor. This consists of two chains, one containing electrons and the other one holes, hosted by arrays of double quantum dots. The two chains are in close proximity and embedded in the same photonic cavity, in the same spirit of the Dicke model. We find the phase diagram of this model showing that, when transitioning from the ferro/antiferromagnetic to the superradiant phase, the quantum capacitance of the model is greatly enhanced.

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40

Gils, Charlotte. "Ashkin–Teller universality in a quantum double model of Ising anyons." Journal of Statistical Mechanics: Theory and Experiment 2009, no. 07 (July 9, 2009): P07019. http://dx.doi.org/10.1088/1742-5468/2009/07/p07019.

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41

Su-Zhen, Luan, and Liu Hong-Xia. "Quantum compact model for thin-body double-gate Schottky barrier MOSFETs." Chinese Physics B 17, no. 8 (August 2008): 3077–82. http://dx.doi.org/10.1088/1674-1056/17/8/051.

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42

Isić, G., D. Indjin, V. Milanović, J. Radovanović, Z. Ikonić, and P. Harrison. "A quantum transport model for the double-barrier nonmagnetic spin filter." Journal of Physics: Conference Series 242 (July 1, 2010): 012008. http://dx.doi.org/10.1088/1742-6596/242/1/012008.

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43

ElKashlan, Rana Y., Omnia Samy, Azza Anis, Yehea Ismail, and Hamdy Abdelhamid. "Unified Quantum and Reliability Model for Ultra-Thin Double-Gate MOSFETs." Silicon 12, no. 1 (February 6, 2019): 21–28. http://dx.doi.org/10.1007/s12633-019-0096-1.

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44

Noteborn, H. J. M. F., H. P. Joosten, K. Kaski, and D. Lenstra. "Alternative for the quantum inductance model in double-barrier resonant-tunneling." Superlattices and Microstructures 13, no. 2 (March 1993): 153. http://dx.doi.org/10.1006/spmi.1993.1028.

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KRÁL, K., Z. KHÁS, P. ZDENĚK, M. ČERŇANSKÝ, and C. Y. LIN. "ELECTRON-ENERGY RELAXATION IN POLAR SEMICONDUCTOR DOUBLE QUANTUM DOTS." International Journal of Modern Physics B 15, no. 27 (October 30, 2001): 3503–12. http://dx.doi.org/10.1142/s0217979201007403.

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The zero-dimensional semiconductor nanostructures belong to the candidates for the realization of the quantum bits. They are expected to be scalable for the purpose of tuning their physical properties. In these structures the quantum bit could be realized in the form of a single quantum dot with two electronic energy levels, with only one electron in the dot. As the basic states of the quantum bit, realized in this way, the two orbital states of the electron in the dot could be used. It appears however that usually the relaxation of the energy of the electron from the excited energy level is often rather fast in the polar semiconductor quantum dots. It is the purpose of this paper to present calculations of the relaxation rate of the electron in an asymmetric pair of tunneling coupled quantum dots, in which the two electronic orbitals of the quantum bit are located each in a separate dot. The calculation of the electronic energy relaxation is based on the multiple electron-LO-phonon scattering processes, implemented to the theory via the electronic self-energy taken in the self-consistent Born approximation. The dependence of the relaxation rate on the geometry of the pair of the coupled dots and on the lattice temperature is presented for a realistic model of this nanostructure.

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46

Huang, Danhong, Yang Zhao, and Eddie Awad. "Linear and Nonlinear Optical Responses in Double Quantum Wells with Field Induced Quantum Coherence and Interference." Journal of Nonlinear Optical Physics & Materials 06, no. 02 (June 1997): 119–39. http://dx.doi.org/10.1142/s0218863597000113.

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New results of quantum coherence and interference effects in linear and nonlinear optical responses in double quantum wells are presented. Three-subband model in which two upper tunneling-split subbands are coupled by a dc-field is studied. We show the importance of the dc-field in establishing the quantum coherence and interference which introduces into the lasing without inversion and enhances the optical nonlinearity in the system. The optimal threshold dc-field can achieve as low as 4 kV/cm in our model. The Coulomb renormalization of electron kinetic energy is included. The many-body theory is employed to calculate both the linear and nonlinear optical responses.

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47

XIONG, HUA-HUI, TAOTAO QIU, YI-FU CAI, and XINMIN ZHANG. "CYCLIC UNIVERSE WITH QUINTOM MATTER IN LOOP QUANTUM COSMOLOGY." Modern Physics Letters A 24, no. 15 (May 20, 2009): 1237–46. http://dx.doi.org/10.1142/s0217732309030667.

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In this paper, we study the possibility of model building of cyclic universe with Quintom matter in the framework of Loop Quantum Cosmology. After a general demonstration, we provide two examples, one with double-fluid and another double-scalar field, to show how such a scenario is obtained. Analytical and numerical calculations are both presented in the paper.

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48

ZHANG, X. Y. "QUANTUM MONTE CARLO ALGORITHM FOR CONSTRAINED FERMIONS." Modern Physics Letters B 05, no. 19 (August 20, 1991): 1255–65. http://dx.doi.org/10.1142/s0217984991001532.

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Using path integral quantization in the subspace that forbids double occupancy, we introduce a quantum Monte Carlo algorithm for simulation of fermion models with constraint. The algorithm can be applied to a class of lattice fermion models, including the infinite-U Hubbard model and the t - J model.

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49

Sasaki, M. "Toward implementation of coding for quantum sources and channels." Quantum Information and Computation 4, no. 6&7 (December 2004): 526–36. http://dx.doi.org/10.26421/qic4.6-7-11.

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We review our experiment on quantum source and channel codings, the most fundamental operations in quantum info-communications. For both codings, entangling letter states is essential. Our model is based on the polarization-location coding, and a quasi-single photon linear optics implementation to entangle the polarization and location degrees of freedom. Using single-photon events in a subset of possible cases, we simulate quantum coding-decoding operations for nonorthogonal states under the quasi-pure state condition. In the quantum channel coding, we double the spatial bandwidth (number of optical paths), and demonstrate the information more than double can be transmitted. In the quantum source coding, we halve the spatial bandwidth to compress the data and decompress the original data with the high fidelity approaching the theoretical limit.

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KUO, DAVID M. T. "INFRARED WAVELENGTH QUANTUM COMMUNICATIONS BASED ON SINGLE ELECTRON TRANSISTORS." International Journal of Quantum Information 03, supp01 (November 2005): 163–72. http://dx.doi.org/10.1142/s0219749905001353.

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We propose to employ a selective formation method to embed an isolated self assembled quantum dot into a n-i-n junction to implement single electron transistors (SETs). The absorption and emission spectrum of SETs are theoretically studied by the Keldysh Green function method. The electronic levels and Coulomb interactions of electrons of InAs quantum dot (QD) are evaluated by an effective mass model. It is found that Coulomb interaction and level mixing in the many body open system lead to double peaks associated with the intraband transitions involving two lowest levels of the QD. We can electrically control the SETs as a single-photon source and double-photon source for 10 μm wavelength. The single photon source can be used in the application of quantum cryptograph, and the double-photon source can be utilized in the teleportation.

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