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Journal articles on the topic 'Perturbation (Quantum dynamics); Quantum electrodynamics'

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Author: Grafiati

Published: 10 December 2022

Last updated: 28 January 2023

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1

Teixeira, W. S., F. L. Semião, J. Tuorila, and M. Möttönen. "Assessment of weak-coupling approximations on a driven two-level system under dissipation." New Journal of Physics 24, no. 1 (December 31, 2021): 013005. http://dx.doi.org/10.1088/1367-2630/ac43ee.

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Abstract The standard weak-coupling approximations associated to open quantum systems have been extensively used in the description of a two-level quantum system, qubit, subjected to relatively weak dissipation compared with the qubit frequency. However, recent progress in the experimental implementations of controlled quantum systems with increased levels of on-demand engineered dissipation has motivated precision studies in parameter regimes that question the validity of the approximations, especially in the presence of time-dependent drive fields. In this paper, we address the precision of weak-coupling approximations by studying a driven qubit through the numerically exact and non-perturbative method known as the stochastic Liouville–von Neumann equation with dissipation. By considering weak drive fields and a cold Ohmic environment with a high cutoff frequency, we use the Markovian Lindblad master equation as a point of comparison for the SLED method and study the influence of the bath-induced energy shift on the qubit dynamics. We also propose a metric that may be used in experiments to map the regime of validity of the Lindblad equation in predicting the steady state of the driven qubit. In addition, we study signatures of the well-known Mollow triplet and observe its meltdown owing to dissipation in an experimentally feasible parameter regime of circuit electrodynamics. Besides shedding light on the practical limitations of the Lindblad equation, we expect our results to inspire future experimental research on engineered open quantum systems, the accurate modeling of which may benefit from non-perturbative methods.

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CRATER, HORACE W., CHUN WA WONG, and CHEUK-YIN WONG. "SINGULARITY-FREE BREIT EQUATION FROM CONSTRAINT TWO-BODY DIRAC EQUATIONS." International Journal of Modern Physics E 05, no. 04 (December 1996): 589–615. http://dx.doi.org/10.1142/s0218301396000323.

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We examine the relation between two approaches to the quantum relativistic two-body problem: (1) the Breit equation, and (2) the two-body Dirac equations derived from constraint dynamics. In applications to quantum electrodynamics, the former equation becomes pathological if certain interaction terms are not treated as perturbations. The difficulty comes from singularities which appear at finite separations r in the reduced set of coupled equations for attractive potentials even when the potentials themselves are not singular there. They are known to give rise to unphysical bound states and resonances. In contrast, the two-body Dirac equations of constraint dynamics do not have these pathologies in many nonperturbative treatments. To understand these marked differences we first express these contraint equations, which have an “external potential” form, similar to coupled one-body Dirac equations, in a hyperbolic form. These coupled equations are then recast into two equivalent equations: (1) a covariant Breit-like equation with potentials that are exponential functions of certain “generator” functions, and (2) a covariant orthogonality constraint on the relative momentum. This reduction enables us to show in a transparent way that finite-r singularities do not appear as long as the exponential structure is not tampered with and the exponential generators of the interaction are themselves nonsingular for finite r. These Dirac or Breit equations, free of the structural singularities which plague the usual Breit equation, can then be used safely under all circumstances, encompassing numerous applications in the fields of particle, nuclear, and atomic physics which involve highly relativistic and strong binding configurations.

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3

Lindgren, Ingvar, Sten Salomonson, and Daniel Hedendahl. "New approach to many-body quantum-electrodynamics calculations:merging quantum electrodynamics with many-body perturbation." Canadian Journal of Physics 83, no. 4 (April 1, 2005): 395–403. http://dx.doi.org/10.1139/p05-012.

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A new method for bound-state quantum electrodynamics (QED) calculations on many-electron systems is presented that is a combination of the non-QED many-body technique for quasi-degenerate systems and the newly developed covariant-evolution-operator technique for QED calculations. The latter technique has been successfully applied to the fine structure of excited states of medium-heavy heliumlike ions, and it is expected that the new method should be applicable also to light elements, hopefully down to neutral helium. PACS Nos.: 31.30.Jv, 31.15.Md, 31.25.Jf, 33.15.Pw

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4

Lindgren, Ingvar, Sten Salomonson, and Daniel Hedendahl. "Combining Many-Body Perturbation and Quantum Electrodynamics." Journal of Atomic, Molecular, and Optical Physics 2011 (December 18, 2011): 1–11. http://dx.doi.org/10.1155/2011/723574.

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It has been a long-sought problem to be able to combine many-body perturbation theory and quantum electrodynamics into a unified, covariant model. Such a model has recently been developed at our laboratory and is outlined in the present paper. The model has potential applications in many areas and opens up the possibility of studying the interplay between various interactions in different system. The model has so far been applied to highly ionized helium-like ions, and some numerical results are given. It is expected that the combined effect—that has never been calculated before—could have a significant effect on certain experimental data. The radiative effects are being regularized using the dimensional regularization in Coulomb gauge, and the first numerical results have been obtained.

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5

FIALKOVSKI, I. V., V. N. MARKOV, and YU M. PIS'MAK. "FIELD OF HOMOGENEOUS PLANE IN QUANTUM ELECTRODYNAMICS." International Journal of Modern Physics A 21, no. 12 (May 10, 2006): 2601–16. http://dx.doi.org/10.1142/s0217751x06029053.

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We study quantum electrodynamics coupled to the matter field on singular background, which we call defect. For defect on the infinite plane we calculated the fermion propagator and mean electromagnetic field. We show that at large distances from the defect plane, the electromagnetic field is constant what is in agreement with the classical results. The quantum corrections determining the field near the plane are calculated in the leading order of perturbation theory.

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6

Veklenko, Boris A. "Energy, Information, and Superluminal Speed in Quantum Electrodynamics." Light & Engineering, no. 04-2020 (August 2020): 27–33. http://dx.doi.org/10.33383/2019-097.

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Without using the perturbation theory, the article demonstrates a possibility of superluminal information-carrying signals in standard quantum electrodynamics using the example of scattering of quantum electromagnetic field by an excited atom.

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7

Gao Deying, 高德营, and 夏云杰 Xia Yunjie. "Quantum Correlation Dynamics of Motive Atoms in Cavity Quantum Electrodynamics." Laser & Optoelectronics Progress 52, no. 8 (2015): 082701. http://dx.doi.org/10.3788/lop52.082701.

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8

GIROTTI, H. O., M. GOMES, and A. J. DA SILVA. "INFRARED STRUCTURE OF (2 + 1)-DIMENSIONAL QUANTUM ELECTRODYNAMICS." Modern Physics Letters A 09, no. 29 (September 21, 1994): 2699–704. http://dx.doi.org/10.1142/s0217732394002549.

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The Bloch–Nordsieck approximation is used to study the ir structure of quantum electrodynamics in 2 + 1 dimensions. Unlike in QED 4, the ir singularities occurring in each order of perturbation theory do not add up to a finite limit. However, the resummation of vacuum polarization graphs is shown to induce a mass which solves the ir problem.

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9

Manzalini, Antonio, and Bruno Galeazzi. "Explaining Homeopathy with Quantum Electrodynamics." Homeopathy 108, no. 03 (March 22, 2019): 169–76. http://dx.doi.org/10.1055/s-0039-1681037.

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Background Every living organism is an open system operating far from thermodynamic equilibrium and exchanging energy, matter and information with an external environment. These exchanges are performed through non-linear interactions of billions of different biological components, at different levels, from the quantum to the macro-dimensional. The concept of quantum coherence is an inherent property of living cells, used for long-range interactions such as synchronization of cell division processes. There is support from recent advances in quantum biology, which demonstrate that coherence, as a state of order of matter coupled with electromagnetic (EM) fields, is one of the key quantum phenomena supporting life dynamics. Coherent phenomena are well explained by quantum field theory (QFT), a well-established theoretical framework in quantum physics. Water is essential for life, being the medium used by living organisms to carry out various biochemical reactions and playing a fundamental role in coherent phenomena. Methods Quantum electrodynamics (QED), which is the relativistic QFT of electrodynamics, deals with the interactions between EM fields and matter. QED provides theoretical models and experimental frameworks for the emergence and dynamics of coherent structures, even in living organisms. This article provides a model of multi-level coherence for living organisms in which fractal phase oscillations of water are able to link and regulate a biochemical reaction. A mathematical approach, based on the eigenfunctions of Laplace operator in hyper-structures, is explored as a valuable framework to simulate and explain the oneness dynamics of multi-level coherence in life. The preparation process of a homeopathic medicine is analyzed according to QED principles, thus providing a scientific explanation for the theoretical model of “information transfer” from the substance to the water solution. A subsequent step explores the action of a homeopathic medicine in a living organism according to QED principles and the phase-space attractor's dynamics. Results According to the developed model, all levels of a living organism—organelles, cells, tissues, organs, organ systems, whole organism—are characterized by their own specific wave functions, whose phases are perfectly orchestrated in a multi-level coherence oneness. When this multi-level coherence is broken, a disease emerges. An example shows how a homeopathic medicine can bring back a patient from a disease state to a healthy one. In particular, by adopting QED, it is argued that in the preparation of homeopathic medicines, the progressive dilution/succussion processes create the conditions for the emergence of coherence domains (CDs) in the aqueous solution. Those domains code the original substance information (in terms of phase oscillations) and therefore they can transfer said information (by phase resonance) to the multi-level coherent structures of the living organism. Conclusions We encourage that QED principles and explanations become embodied in the fundamental teachings of the homeopathic method, thus providing the homeopath with a firm grounding in the practice of rational medicine. Systematic efforts in this direction should include multiple disciplines, such as quantum physics, quantum biology, conventional and homeopathic medicine and psychology.

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10

Dorokhov, A. E., A. A. Krutov, A. P. Martynenko, F. A. Martynenko, and O. S. Sukhorukova. "Energy spectra of muonic atoms in quantum electrodynamics." EPJ Web of Conferences 204 (2019): 05007. http://dx.doi.org/10.1051/epjconf/201920405007.

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Vacuum polarization, nuclear structure and recoil, radiative corrections to the hyperfine structure of S-states in muonic ions of lithium, beryllium and boron are calculated on the basis of quasipotential method in quantum electrodynamics. We consider contributions in first and second orders of perturbation theory which have the order α5 and α6 in the energy spectrum. Total values of hyperfine splittings are obtained which can be used for a comparison with future experimental data.

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11

Stumpf, H., B. Fauser, and W. Pfister. "Composite Particle Theory in Quantum Electrodynamics." Zeitschrift für Naturforschung A 48, no. 7 (July 1, 1993): 765–76. http://dx.doi.org/10.1515/zna-1993-0705.

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Abstract Without use of pathintegral formalism a composite particle effective dynamics is developed for spinor quantum electrodynamics. By algebraic evaluation of spinor quantum electrodynamics in Coulomb gauge a corresponding functional equation is derived. The commutation rules for the transversal electromagnetic field can be deduced as a consequence of this formalism. By application of weak mapping theorems the QED functional equation can be mapped onto a functional equation for composite particles with mutual interaction and interaction with the electromagnetic field. The formalism is demonstrated for positronium states. The incorporation of renormalization into this scheme is verified.

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12

SEKE, JOSIP. "AN ELEMENTARY UNAMBIGUOUS, COMPLETE RENORMALIZATION PROCEDURE IN NONRELATIVISTIC QUANTUM ELECTRODYNAMICS." Modern Physics Letters B 13, no. 01 (January 10, 1999): 27–32. http://dx.doi.org/10.1142/s0217984999000051.

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A new unambiguous, complete renormalization procedure is presented. Without introducing any energy (or mass) counter terms, by using the elementary time-dependent perturbation theory, it is shown that the renormalization procedure is equivalent to the identification and removement of those terms which stem from the experimentally unobservable free-electron–vacuum-field interaction.

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13

AZAM, MOFAZZAL. "SOME COMMENTS ON THE DIVERGENCE OF PERTURBATION SERIES IN QUANTUM ELECTRODYNAMICS." Modern Physics Letters A 21, no. 14 (May 10, 2006): 1161–66. http://dx.doi.org/10.1142/s0217732306019463.

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It has been argued by Dyson that the perturbation theory in coupling constant in QED cannot be convergent. We find that similar albeit slightly different arguments lead to the divergence of the series of 1/N f expansion in QED.

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14

Brookes, Paul, Giovanna Tancredi, Andrew D. Patterson, Joseph Rahamim, Martina Esposito, Themistoklis K. Mavrogordatos, Peter J. Leek, Eran Ginossar, and Marzena H. Szymanska. "Critical slowing down in circuit quantum electrodynamics." Science Advances 7, no. 21 (May 2021): eabe9492. http://dx.doi.org/10.1126/sciadv.abe9492.

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Critical slowing down of the time it takes a system to reach equilibrium is a key signature of bistability in dissipative first-order phase transitions. Understanding and characterizing this process can shed light on the underlying many-body dynamics that occur close to such a transition. Here, we explore the rich quantum activation dynamics and the appearance of critical slowing down in an engineered superconducting quantum circuit. Specifically, we investigate the intermediate bistable regime of the generalized Jaynes-Cummings Hamiltonian (GJC), realized by a circuit quantum electrodynamics (cQED) system consisting of a transmon qubit coupled to a microwave cavity. We find a previously unidentified regime of quantum activation in which the critical slowing down reaches saturation and, by comparing our experimental results with a range of models, we shed light on the fundamental role played by the qubit in this regime.

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15

Madsen, K. H., and P. Lodahl. "Quantitative analysis of quantum dot dynamics and emission spectra in cavity quantum electrodynamics." New Journal of Physics 15, no. 2 (February 7, 2013): 025013. http://dx.doi.org/10.1088/1367-2630/15/2/025013.

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16

Lindgren, Ingvar. "Development of many-body perturbation theory: How to combine with quantum electrodynamics." International Journal of Quantum Chemistry 114, no. 18 (February 28, 2014): 1176–82. http://dx.doi.org/10.1002/qua.24629.

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17

Boldo, J. L., B. M. Pimentel, and J. L. Tomazelli. "Infrared dynamics in (2+1) dimensions." Canadian Journal of Physics 76, no. 1 (January 1, 1998): 69–76. http://dx.doi.org/10.1139/p97-046.

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In this work we study the asymptotic behavior of (2+1)-dimensional quantum electrodynamics in the infrared region. We show that an appropriate redefinition of the fermion current operator leads to an asymptotic evolution operator that contains a divergent Coulomb phase factor and a contribution from the electromagnetic field at large distances, factored from the evolution operator for free fields, and we conclude that the modified scattering operator maps two spaces of coherent states of the electromagnetic field, as in the KulishFaddeev model for QED (quantum electrodynamics) in four space-time dimensions. PACS No. 11.10Kk, 11.55m

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18

Ardenghi, Juan Sebastián. "Entanglement entropy between virtual and real excitations in quantum electrodynamics." International Journal of Modern Physics A 33, no. 13 (May 9, 2018): 1850081. http://dx.doi.org/10.1142/s0217751x18500811.

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The aim of this work is to introduce the entanglement entropy of real and virtual excitations of fermion and photon fields. By rewriting the generating functional of quantum electrodynamics theory as an inner product between quantum operators, it is possible to obtain quantum density operators representing the propagation of real and virtual particles. These operators are partial traces, where the degrees of freedom traced out are unobserved excitations. Then the von Neumann definition of entropy can be applied to these quantum operators and in particular, for the partial traces taken over by the internal or external degrees of freedom. A universal behavior is obtained for the entanglement entropy for different quantum fields at zeroth order in the coupling constant. In order to obtain numerical results at different orders in the perturbation expansion, the Bloch–Nordsieck model is considered, where it is shown that for some particular values of the electric charge, the von Neumann entropy increases or decreases with respect to the noninteracting case.

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19

NEZNAMOV, V. P. "ELECTRON SELF-ENERGY IN PSEUDO-HERMITIAN QUANTUM ELECTRODYNAMICS WITH A MAXIMAL MASS M." International Journal of Geometric Methods in Modern Physics 08, no. 05 (August 2011): 1007–19. http://dx.doi.org/10.1142/s0219887811005518.

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The electron self-energy (self-mass) is calculated on the basis of the model of quantum field theory with maximal mass M, developed by V. G. Kadyshevsky et al. within the pseudo-Hermitian quantum electrodynamics in the second order of the perturbation theory. In theory, there is the natural cut-off of large transmitted momentum in intermediate states because of presence of the universal mass M. As a result, the electron self-mass is finite and depends on the transmitted maximum momentum [Formula: see text]. Two interpretations of the obtained results are possible at defined M and A. The first interpretation allows confirming quantitatively the old concept of elementary particle mass sources defined by interaction of particles with self-gauge fields. The second interpretation results in the possibility not to renormalize the mass (at least in the second order of perturbation theory) owing to the zero mass operator ∑(p).

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20

Tachibana, Akitomo. "New aspects of quantum electrodynamics on electronic structure and dynamics." Journal of Computational Chemistry 40, no. 2 (October 9, 2018): 316–27. http://dx.doi.org/10.1002/jcc.25600.

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21

Flick, Johannes, Nicholas Rivera, and Prineha Narang. "Strong light-matter coupling in quantum chemistry and quantum photonics." Nanophotonics 7, no. 9 (September 8, 2018): 1479–501. http://dx.doi.org/10.1515/nanoph-2018-0067.

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AbstractIn this article, we review strong light-matter coupling at the interface of materials science, quantum chemistry, and quantum photonics. The control of light and heat at thermodynamic limits enables exciting new opportunities for the rapidly converging fields of polaritonic chemistry and quantum optics at the atomic scale from a theoretical and computational perspective. Our review follows remarkable experimental demonstrations that now routinely achieve the strong coupling limit of light and matter. In polaritonic chemistry, many molecules couple collectively to a single-photon mode, whereas, in the field of nanoplasmonics, strong coupling can be achieved at the single-molecule limit. Theoretical approaches to address these experiments, however, are more recent and come from a spectrum of fields merging new developments in quantum chemistry and quantum electrodynamics alike. We review these latest developments and highlight the common features between these two different limits, maintaining a focus on the theoretical tools used to analyze these two classes of systems. Finally, we present a new perspective on the need for and steps toward merging, formally and computationally, two of the most prominent and Nobel Prize-winning theories in physics and chemistry: quantum electrodynamics and electronic structure (density functional) theory. We present a case for how a fully quantum description of light and matter that treats electrons, photons, and phonons on the same quantized footing will unravel new quantum effects in cavity-controlled chemical dynamics, optomechanics, nanophotonics, and the many other fields that use electrons, photons, and phonons.

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Salam, A. "The Unified Theory of Resonance Energy Transfer According to Molecular Quantum Electrodynamics." Atoms 6, no. 4 (October 11, 2018): 56. http://dx.doi.org/10.3390/atoms6040056.

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An overview is given of the molecular quantum electrodynamical (QED) theory of resonance energy transfer (RET). In this quantized radiation field description, RET arises from the exchange of a single virtual photon between excited donor and unexcited acceptor species. Diagrammatic time-dependent perturbation theory is employed to calculate the transfer matrix element, from which the migration rate is obtained via the Fermi golden rule. Rate formulae for oriented and isotropic systems hold for all pair separation distances, R, beyond wave function overlap. The two well-known mechanisms associated with migration of energy, namely the R−6 radiationless transfer rate due to Förster and the R−2 radiative exchange, correspond to near- and far-zone asymptotes of the general result. Discriminatory pair transfer rates are also presented. The influence of an environment is accounted for by invoking the polariton, which mediates exchange and by introducing a complex refractive index to describe local field and screening effects. This macroscopic treatment is compared and contrasted with a microscopic analysis in which the role of a neutral, polarizable and passive third-particle in mediating transfer of energy is considered. Three possible coupling mechanisms arise, each requiring summation over 24 time-ordered diagrams at fourth-order of perturbation theory with the total rate being a sum of two- and various three-body terms.

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23

AKHMETELI, ANDREY. "IS NO DRAMA QUANTUM THEORY POSSIBLE?" International Journal of Quantum Information 09, supp01 (January 2011): 17–26. http://dx.doi.org/10.1142/s0219749911006909.

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The matter field can be naturally eliminated from the equations of the Klein-Gordon-Maxwell electrodynamics in the unitary gauge. The resulting equations describe independent dynamics of the electromagnetic field: if components of the 4-potential of the electromagnetic field and their first derivatives with respect to time are known in the entire space at some time point, the values of their second derivatives with respect to time can be calculated for the same time point, so the Cauchy problem can be posed, and integration yields the 4-potential in the entire space-time. This surprising result both permits mathematical simplification and can be useful for interpretation of quantum theory. For example, in the Bohm interpretation, the electromagnetic field can replace the wave function as the guiding field. Independent of the interpretation, quantum phenomena can be described in terms of electromagnetic field only. For the system of nonlinear partial differential equations of the Klein-Gordon-Maxwell electrodynamics, a generalized Carleman linearization procedure generates a system of linear equations in the Hilbert space, which looks like a second-quantized theory and is equivalent to the original nonlinear system on the set of solutions of the latter. Similar, but less general results are obtained for the Dirac-Maxwell electrodynamics.

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24

Romero, Rodolfo, and Gustavo Aucar. "Self-energy Effects on Nuclear Magnetic Resonance Parameters within Quantum Electrodynamics Perturbation Theory." International Journal of Molecular Sciences 3, no. 8 (August 31, 2002): 914–30. http://dx.doi.org/10.3390/i3080914.

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25

Kanda, A., M. Prunescu, and R. Wong. "Quantizing dynamics." Journal of Physics: Conference Series 2197, no. 1 (March 1, 2022): 012027. http://dx.doi.org/10.1088/1742-6596/2197/1/012027.

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Abstract In theoretical physics, quantization means reducing a continuum structure to discrete structure. This process was widely used in the development of quantum mechanics since Planck’s convention of the discretization of the energy of electromagnetic (EM) waves e = nhf as a solution to the crisis of the blackbody radiation. When combined with Einstein’s relativistic particle energy equation e = mc 2 it became a most fundamental process of the 20th century theoretical physics. Planck was reluctant to consider his energy quanta e = nhf as a physical particle. His concern was forgotten in the process of development of quantum mechanics, which was Einstein’s relativity theory dynamics combined with Planck’s wave-particle duality. This framework was later extended by Dirac into the quantization of the entire EM field theory of Maxwell in which the EM fields, which are mathematically a continuous structure, themselves were quantized in terms of Einstein’s special theory of relativity dynamics using Fourier expansions. As it appears that the mathematical error of using wave numbers, which form a real continuum, as indexes of the Fourier expansion for the discretization of waves went unnoticed, this quantization of electrodynamics, called quantum electrodynamics (QED), became a model for further quantizing continuum based physical theories. This error was thus passed down to all of the successors of QED. The theory of quantum gravity is yet another attempt to quantize a major force field theory of gravitational forces. Here as well the issue of the difference between the continuum and the discrete was overlooked.

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Bufalo, R., B. M. Pimentel, and D. E. Soto. "Normalizability analysis of the generalized quantum electrodynamics from the causal point of view." International Journal of Modern Physics A 32, no. 27 (September 30, 2017): 1750165. http://dx.doi.org/10.1142/s0217751x17501652.

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The causal perturbation theory is an axiomatic perturbative theory of the S-matrix. This formalism has as its essence the following axioms: causality, Lorentz invariance and asymptotic conditions. Any other property must be showed via the inductive method order-by-order and, of course, it depends on the particular physical model. In this work we shall study the normalizability of the generalized quantum electrodynamics in the framework of the causal approach. Furthermore, we analyze the implication of the gauge invariance onto the model and obtain the respective Ward–Takahashi–Fradkin identities.

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Poltavsky, Igor, and Alexandre Tkatchenko. "Modeling quantum nuclei with perturbed path integral molecular dynamics." Chemical Science 7, no. 2 (2016): 1368–72. http://dx.doi.org/10.1039/c5sc03443d.

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Filinov, Vladimir, and Alexander Larkin. "Quantum Dynamics of Charged Fermions in the Wigner Formulation of Quantum Mechanics." Universe 4, no. 12 (November 23, 2018): 133. http://dx.doi.org/10.3390/universe4120133.

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To study the kinetic properties of dense quantum plasma, a new quantum dynamics method in the Wigner representation of quantum mechanics has been developed for extreme conditions, when analytical approximations based on different kinds of perturbation theories cannot be applied. This method combines the Feynman and Wigner formulation of quantum mechanics and uses for calculation the path integral Monte-Carlo (WPIMC) in phase space and quantum generalization of the classical molecular dynamics methods (WMD) allowing to solve the quantum Wigner–Liouville-like equation. The Fermi–Dirac statistical effects are accounted for by the effective pair pseudopotential depending on coordinates and momenta and allowing to avoid the famous “sign problem” due to realization of the Pauli blocking of fermions. Significant influence of the interparticle interaction on the high energy asymptotics of the momentum distribution functions have been observed. According to the quantum Kubo formula, we also study the electron conductivity of dense plasma media.

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Viehmann, Oliver, Jan von Delft, and Florian Marquardt. "The quantum transverse-field Ising chain in circuit quantum electrodynamics: effects of disorder on the nonequilibrium dynamics." New Journal of Physics 15, no. 3 (March 12, 2013): 035013. http://dx.doi.org/10.1088/1367-2630/15/3/035013.

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Wang, Siwei, Gregory D. Scholes, and Liang-Yan Hsu. "Quantum dynamics of a molecular emitter strongly coupled with surface plasmon polaritons: A macroscopic quantum electrodynamics approach." Journal of Chemical Physics 151, no. 1 (July 7, 2019): 014105. http://dx.doi.org/10.1063/1.5100014.

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31

Wilkinson, Michael, and Elizabeth J. Austin. "Dynamics of a generic quantum system under a periodic perturbation." Physical Review A 46, no. 1 (July 1, 1992): 64–74. http://dx.doi.org/10.1103/physreva.46.64.

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32

Sukharev, Yury I., Boris A. Markov, and Inna Yu Apalikova. "Electrodynamics of colloidal tin oxyhydrate as a quantum macrosystem." Butlerov Communications 59, no. 8 (August 31, 2019): 1–23. http://dx.doi.org/10.37952/roi-jbc-01/19-59-8-1.

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Pulsation spurts of clusters determining nanocurrent ferroelectric electricity of gel tin oxyhydrates are shown experimentally, which characterizes macroscopic quantum coherent effects induced by a nonstationary magnetic field in the dynamics of high-spin magnetic nanocurrent clusters in a gel matrix. The polyhedral Coxeter model of the tin oxyhydrate Pattern, which is used to make gel objects, is considered, and specific cluster structures are calculated. The experimental geometry of Coxeter polyhedra is described by a gram matrix, where the values of the matrix are cosines of the slope angles of the faces of WHITNEY oxyhydrate structures. Matrix description of the structure of the oxyhydrate, for example, for 42 days (165-231 min.) of aging, allowed to quantify the structural features of polyhedra or the so-called Whitney folds, which form the electromagnetic wave fronts of energy caused by nanocurrent polarization of oxyhydrate polyhedra. Quantitatively, the Whitney folds are determined by calculating the trace or hole of the corresponding gram matrix. The Coxeter polyhedra of the oxyhydrate gel are constructed mainly from cluster five-vertices, which in time can compete isomorphically with the facet 30, 20, 14, 12, and 6 vertices. This determines the fine structure of the gel axiology conformations during aging. The probability of the formation of 30 vertices in the gel of tin oxyhydrate is one of the highest.

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Малышев, А. В., Ю. С. Кожедуб, И. С. Анисимова, Д. А. Глазов, М. Ю. Кайгородов, И. И. Тупицын, and В. М. Шабаев. "Энергия связи основного состояния бериллиеподобного молибдена: корреляционные и квантово-электродинамические эффекты." Оптика и спектроскопия 129, no. 5 (2021): 559. http://dx.doi.org/10.21883/os.2021.05.50882.1814-21.

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High-precision calculations of the ground-state binding energy of berylliumlike molybdenum ($Z=42$) are performed. The applied approach merges rigorous quantum-electrodynamics (QED) treatment up to the second order of perturbation theory in the framework of the Furry picture and the third- and higher-order correlation effects evaluated within the Breit approximation. The mixing of the close configurations of the same symmetry due to the electron--electron interaction is considered by employing the QED perturbation theory for quasi-degenerate levels. The most accurate up-to-date theoretical predictions for the binding energy are obtained.

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34

Cong, Yang, Yu Zhai, Jitai Yang, Adam Grofe, Jiali Gao, and Hui Li. "Quantum vibration perturbation approach with polyatomic probe in simulating infrared spectra." Physical Chemistry Chemical Physics 24, no. 2 (2022): 1174–82. http://dx.doi.org/10.1039/d1cp04490g.

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Lodahl, Peter, and Søren Stobbe. "Solid-state quantum optics with quantum dots in photonic nanostructures." Nanophotonics 2, no. 1 (February 1, 2013): 39–55. http://dx.doi.org/10.1515/nanoph-2012-0039.

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AbstractQuantum nanophotonics has become a new research frontier where quantum optics is combined with nanophotonics in order to enhance and control the interaction between strongly confined light and quantum emitters. Such progress provides a promising pathway towards quantum-information processing on an all-solid-state platform. Here we review recent progress on experiments with quantum dots in nanophotonic structures with special emphasis on the dynamics of single-photon emission. Embedding the quantum dots in photonic band-gap structures offers a way of controlling spontaneous emission of single photons to a degree that is determined by the local light-matter coupling strength. Introducing defects in photonic crystals implies new functionalities. For instance, efficient and strongly confined cavities can be constructed enabling cavity-quantum-electrodynamics experiments. Furthermore, the speed of light can be tailored in a photonic-crystal waveguide forming the basis for highly efficient single-photon sources where the photons are channeled into the slowly propagating mode of the waveguide. Finally, we will discuss some of the surprises that arise in solid-state implementations of quantum-optics experiments in comparison to their atomic counterparts. In particular, it will be shown that the celebrated point-dipole description of light-matter interaction can break down when quantum dots are coupled to plasmon nanostructures.

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BODE, ACHIM, THOMAS LIPPERT, KLAUS SCHILLING, and PEER UEBERHOLZ. "DETERMINATION OF MONOPOLE CURRENT CLUSTERS IN FOUR-DIMENSIONAL QUANTUM ELECTRODYNAMICS." International Journal of Modern Physics C 04, no. 06 (December 1993): 1205–19. http://dx.doi.org/10.1142/s0129183193000951.

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Magnetic monopole currents are believed to have a strong impact on the Monte Carlo dynamics of compact quantum electrodynamics near the phase transition. We have indications that updating algorithms have to form and to break up monopole current clusters in order to force the tunneling of the system between the coexisting phases, the confined phase and the Coulomb phase. This might be responsible for long lived metastabilities in the time series. We present parallel numerical algorithms which allow the fast identification of clusters of monopole loops, the determination of their topological properties as well as their visualization in the course of a Monte Carlo simulation. The algorithms are implemented on the Connection Machine CM-5. We compare the data parallel programming style with a message passing approach. Complexity and performance are discussed.

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Cavina, Vasco, Andrea Mari, and Vittorio Giovannetti. "Slow Dynamics and Thermodynamics of Open Quantum Systems." Proceedings 12, no. 1 (July 10, 2019): 19. http://dx.doi.org/10.3390/proceedings2019012019.

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We develop a perturbation theory to estimate the finite time corrections around a quasi static trajectory, in which a quantum system is able to equilibrate at each instant with its environment. The results are then applied to non equilibrium thermodynamics, in which context we are able to provide a connection between the irreversible contributions and the microscopic details of the dynamical map generating the evolution. Turning the attention to finite time Carnot engines, we found a universal connection between the spectral density esponent of the hot/cold thermal baths and the efficiency at maximum power, giving also a new interpretation to already known results such as the Curzon-Ahborn and the Schmiedl-Seifert efficiencies.

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Kosasih, J. S., and V. A. Wasesatama. "Non-Markovian entanglement dynamics of three independent qubits within atomic-cavity system." Journal of Physics: Conference Series 2243, no. 1 (June 1, 2022): 012115. http://dx.doi.org/10.1088/1742-6596/2243/1/012115.

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Abstract All realistic quantum systems will interact with their environments. This fact presents challenges to the implementation of quantum systems for practical systems. One of the most important quantum resources is the implementation of entanglement. In this paper, we investigate the interplay between the effects of noisy environments and the dynamics of entanglement. The open quantum system model that will be used is cavity quantum electrodynamics (CQED) with three-qubit interacting independently with a variation of environmental model. We use master equation to describe the dynamics of the open quantum system and a lower bound concurrence (CLBC ) to measure the entanglement of tripartite qubit. We derive the exact dynamics of each model and use CLBC method proposed by Li et.al to visualize entanglement dynamics. By adjusting the environmental parameters, we also found revivals and dark-periods of entanglement which are unique to non-Markovian processes.

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Amorim, R. G. G., F. C. Khanna, A. P. C. Malbouisson, J. M. C. Malbouisson, and A. E. Santana. "Quantum field theory in phase space." International Journal of Modern Physics A 34, no. 08 (March 20, 2019): 1950037. http://dx.doi.org/10.1142/s0217751x19500374.

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The tilde conjugation rule in thermofield dynamics, equivalent to the modular conjugation in a [Formula: see text]-algebra, is used to develop unitary representations of the Poincaré group, where the Hilbert space has the phase space content, a symplectic Hilbert space. The state is described by a quasi-amplitude of probability, which is a sort of wave function in phase space, associated with the Wigner function. The quantum field theory in phase space is then constructed, including the quantization rules for the Klein–Gordon and the Dirac fields, the derivation of the electrodynamics in phase space and elements of a relativistic quantum kinetic theory. Towards a physical interpretation of the theory, propagators are associated with the corresponding Wigner functions. The Feynman rules follow accordingly with vertices similar to those of usual non-Abelian quantum field theories.

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SCHWARTZ, STEVEN D. "A NEW SEMICLASSICAL DYNAMICS FROM THE INTERACTION REPRESENTATION." Journal of Theoretical and Computational Chemistry 04, no. 04 (December 2005): 1093–100. http://dx.doi.org/10.1142/s0219633605001908.

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This paper develops a new semiclassical mechanics from an exact quantum prescription. In this formulation, a zeroth order propagation, rather than Hamiltonian, is specified. The exact, full evolution operator is then given from a specific interaction representation of the evolved "perturbation" Hamiltonian. We then investigate a variety of approximate, semiclassical, and mixed Quantum/Classical methods, along with exact methodologies to evaluate this time dependent interaction Hamiltonian. The approximate full evolution operator can be described in a variety of ways including an iterated Lippman-Schwinger like equation, and an expansion of the perturbation propagator generated from the time evolved Hamiltonian.

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Berman, G. P., D. I. Kamenev, and V. I. Tsifrinovich. "Perturbation approach for nuclear magnetic resonance solid-state quantum computation." Journal of Applied Mathematics 2003, no. 1 (2003): 35–53. http://dx.doi.org/10.1155/s1110757x03110182.

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A dynamics of a nuclear-spin quantum computer with a large number(L=1000)of qubits is considered using a perturbation approach. Small parameters are introduced and used to compute the error in an implementation of an entanglement between remote qubits, using a sequence of radio-frequency pulses. The error is computed up to the different orders of the perturbation theory and tested using exact numerical solution.

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KHEIRANDISH, F., and M. AMOOSHAHI. "RADIATION REACTION AND QUANTUM DAMPED HARMONIC OSCILLATOR." Modern Physics Letters A 20, no. 39 (December 21, 2005): 3025–34. http://dx.doi.org/10.1142/s0217732305018384.

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By taking a Klein–Gordon field as the environment of a harmonic oscillator and using a new method for dealing with quantum dissipative systems (minimal coupling method), we find out the quantum dynamics and radiation reaction for a quantum damped harmonic oscillator. Applying perturbation method, we obtain some transition probabilities indicating the way energy flows between oscillator, reservoir and quantum vacuum.

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ZHAO, XIAN-GENG, and MING JUN ZHU. "TUNNELING TIME BETWEEN TWO BIASED QUANTUM WELLS." Modern Physics Letters B 13, no. 12n13 (June 10, 1999): 385–90. http://dx.doi.org/10.1142/s0217984999000488.

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We study the dynamics of double-well systems under the influence of time-dependent external fields. A tunneling time describing the coherent tunneling between two quantum wells is obtained analytically by the use of perturbation theory. We illustrate two examples to show the advantage of our theory, in which the phenomenon of localization/delocalization can be addressed uniformly by the tunneling time.

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Maxmilian Caligiuri, Luigi. "Quantum (hyper)computation through universal quantum gates in water coherent domains." Journal of Physics: Conference Series 2162, no. 1 (January 1, 2022): 012003. http://dx.doi.org/10.1088/1742-6596/2162/1/012003.

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Abstract According to quantum electrodynamics (QED), liquid water is composed by two phases, the first one characterized by a coherent state in which all the molecules oscillate in phase, the other by a non-coherent state in which they are all non-correlated. In the coherent state, the phase-correlated oscillations take place within macroscopic spatial regions called “coherent domains” (CD), admitting a spectrum of excited energy levels and generating, at their borders, an evanescent coherent e.m. field. When two or more excited CDs are sufficiently close to each other, the overlapping between their evanescent fields gives rise to a novel type of interaction due to the mutual exchange of virtual photons by quantum tunnel effect. Furthermore, when such water coherent domains are enclosed with waveguides consisting of suitable materials and design, these effects are stabilized and enhanced, allowing for the realization of an extended network of interacting coherent domains. In this paper, we’ll discuss how to exploit this dynamics to perform quantum computations by setting-up a set of universal quantum gates and calculate their operational time as a function the main parameters of the proposed physical model. We show this model can represent a basic architecture for a novel kind of quantum hyper-computer, characterized by a very high computational speed and able to overcame some of the main issues currently affecting the quantum computational frameworks so far proposed.

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Mirza, Imran M., and Adriana S. Cruz. "On the dissipative dynamics of entangled states in coupled-cavity quantum electrodynamics arrays." Journal of the Optical Society of America B 39, no. 1 (December 13, 2021): 177. http://dx.doi.org/10.1364/josab.441224.

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Lu Daoming, 卢道明, and 邱昌东 Qiu Changdong. "Tripartite Entanglement Dynamics in the Coupled Cavities Quantum Electrodynamics System via Optical Fibers." Acta Optica Sinica 35, no. 12 (2015): 1202002. http://dx.doi.org/10.3788/aos201535.1202002.

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Leib, Martin, and Michael J. Hartmann. "Bose–Hubbard dynamics of polaritons in a chain of circuit quantum electrodynamics cavities." New Journal of Physics 12, no. 9 (September 22, 2010): 093031. http://dx.doi.org/10.1088/1367-2630/12/9/093031.

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48

Miransky, V. A. "Dynamics of spontaneous chiral symmetry breaking and the continuum limit in quantum electrodynamics." Il Nuovo Cimento A 90, no. 2 (November 1985): 149–70. http://dx.doi.org/10.1007/bf02724229.

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Chen, Hsing-Ta, Tao E. Li, Maxim Sukharev, Abraham Nitzan, and Joseph E. Subotnik. "Ehrenfest+R dynamics. I. A mixed quantum–classical electrodynamics simulation of spontaneous emission." Journal of Chemical Physics 150, no. 4 (January 28, 2019): 044102. http://dx.doi.org/10.1063/1.5057365.

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Wilson, S. "On the use of many-body perturbation theory and quantum-electrodynamics in molecular electronic structure theory." Journal of Molecular Structure: THEOCHEM 547, no. 1-3 (July 2001): 279–91. http://dx.doi.org/10.1016/s0166-1280(01)00477-8.

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