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## Quantum entanglement for two qubits in a nonstationary cavity

Physical Review A: Atomic, Molecular, and Optical physics. 2016. Vol. 94. No. 5. P. 052308.

The quantum entanglement and the probability of the dynamical Lamb effect for two qubits caused by non-adiabatic fast change of the boundary conditions are studied. The conditional concurrence of the qubits for each fixed number of created photons in a nonstationary cavity is obtained as a measure of the dynamical quantum entanglement due to the dynamical Lamb effect. We discuss the physical realization of the dynamical Lamb effect, based on superconducting qubits.

Keywords: Quantum entanglementDynamical Lamb effectsuperconducting qubitsдинамический эффект Лэмбасверхпроводящие кубитыквантовая запутанность

Publication based on the results of:

A.A. Zhukov, D.S. Shapiro, W.V. Pogosov et al., Physical Review B: Condensed Matter and Materials Physics 2016 Vol. 93 P. 063845

Superconducting circuits provide a new platform for study of nonstationary cavity QED phenomena. An example of such a phenomenon is the dynamical Lamb effect, which is the parametric excitation of an atom due to nonadiabatic modulation of its Lamb shift. This effect was initially introduced for a natural atom in a varying cavity, while we ...

Added: October 18, 2016

S. V. Remizov, A. A. Zhukov, W. V. Pogosov et al., Laser Physics Letters 2019 Vol. 16 P. 065205-1-065205-8

We propose a realization of two remarkable effects of Dicke physics in quantum simulation of light-matter many-body interactions with artificial quantum systems. These effects are a superradiant decay of an ensemble of qubits and the opposite radiation trapping effect. We show that both phenomena coexist in the crossover regime of a ‘moderately bad’ single-mode cavity ...

Added: October 22, 2019

А.А. Жуков, С.В. Ремизов, В.В. Погосов et al., Письма в Журнал экспериментальной и теоретической физики 2018 Т. 108 № 1 С. 62-70

Показано, что сверхпроводниковые кубитные системы, благодаря своей высокой перестраиваемости, могут использоваться в качестве платформы для экспериментального исследования различных эффектов нестационарной квантовой электродинамики в полости. Так, за счет неадиабатического изменения эффективной константы взаимодействия между подсистемой кубитов и резонатора можно добиться реализации динамического эффекта Лэмба, который проявляется в возбуждении кубита (атома) при изменении лэмбовского сдвига его уровней. ...

Added: October 22, 2018

D.S. Shapiro, A.A. Zhukov, W.V. Pogosov et al., Physical Review A: Atomic, Molecular, and Optical physics 2015 Vol. 91 No. 6 P. 063814

A natural atom placed into a cavity with time-dependent parameters can be parametrically excited due to interaction with the quantized photon mode. One of the channels for this process is the dynamical Lamb effect, induced by a nonadiabatic modulation of the atomic-level Lamb shift. However, in experiments with natural atoms it is quite difficult to ...

Added: September 8, 2015

Семенов А. А., Satanin Arkady, Journal of Physics: Conference Series 2021 Vol. 1740 Article 012064

We study dynamics of a qubit coupled to a single photon mode in a high-quality resonator. For a weak coupling constant the qubit and photon form a long-lived bound state which may be called as a "photon-qubit atom". We consider the stability and chaotic dynamics of the photon-qubit atom under the action of short electromagnetic ...

Added: June 25, 2021

Марина Валерьевна Денисенко, Николай Викторович Кленов, Сатанин А. М., AIP Conference Proceedings 2018 Vol. 136 P. 020009-020015

The present study is devoted to development of a technique for numerical simulation of the wave function dynamics the single Josephson qubits and arrays of noninteracting qubits controlled by ultra-short pulses. We wish to demonstrate the feasibility of a new principle of basic logical operations on the picosecond timescale. The influence of the unipolar pulse ...

Added: February 21, 2019

V.E. Valiullin, A.V. Mikheyenkov, N.M. Chtchelkatchev et al., Physical Review B: Condensed Matter and Materials Physics 2020 Vol. 102 No. 15 P. 155125

Using the exact diagonalization technique, we determine the energy spectrum and wave functions for finite
chains described by the two-spin (Kugel-Khomskii) model with different types of intersubsystem exchange
terms. The obtained solutions provide the possibility to address the problem of quantum entanglement inherent
in this class of models. We put the main emphasis on the calculations of the ...

Added: November 9, 2020

Arseyev P., Наталья Сергеевна Маслова, The European Physical Journal B 2015 Vol. 88 No. 2 P. 40:1-40:9

We proved that for arbitrary mixed state the concurrence and the entanglement are determined by the average value of electron’s pair correlation functions particular combinations. We analyzed the dynamics of the initial two-electronic state in two interacting single-level quantum dots (QDs) with Coulomb correlations, weakly tunnel coupled with an electronic reservoir. We obtained correlation functions ...

Added: March 17, 2016

Slunyaev A., Анна Витальевна Кокорина, Water Waves, Springer 2019 P. 1-20

The issue of accounting of the wave breaking phenomenon in direct numerical simulations of oceanic waves is discussed. It is emphasized that this problem is crucial for the deterministic description of waves, and also for the dynamical calculation of extreme wave statistical characteristics, such as rogue wave height probability, asymmetry, etc. The conditions for accurate ...

Added: October 13, 2019

Prazdnichnykh A., Glazov M., L. Ren et al., Physical Review B: Condensed Matter and Materials Physics 2021 Vol. 103 No. 8 P. 085302-1-085302-12

The exciton valley dynamics in van der Waals heterostructures with transition metal dichalcogenide monolayers is driven by the long-range exchange interaction between the electron and the hole in the exciton. It couples the states active in the opposite circular polarizations resulting in the longitudinal-transverse splitting of excitons propagating in the monolayer plane. Here we study ...

Added: March 5, 2021

Pelinovsky E., I. Didenkulova, A. Rybkin, Journal of Fluid Mechanics 2014 Vol. 748 P. 416-432

We present an exact analytical solution of the nonlinear shallow water theory for wave run-up in inclined channels of arbitrary cross-section, which generalizes previous studies on wave run-up for a plane beach and channels of parabolic cross-section. The solution is found using a hodograph-type transform, which extends the well-known Carrier–Greenspan transform for wave run-up on ...

Added: November 19, 2014

Marshakov A., Андрей Дмитриевич Миронов, Алексей Юрьевич Морозов, Journal of Geometry and Physics 2011 Vol. 61 P. 1203-1222

We present a summary of current knowledge about the AGT relations for conformal blocks with additional insertion of the simplest degenerate operator, and a special choice of the corresponding intermediate dimension, when the conformal blocks satisfy hypergeometric-type differential equations in position of the degenerate operator. A special attention is devoted to representation of conformal block ...

Added: February 28, 2013

Andrew G. Semenov, Andrei D. Zaikin, Physical Review B: Condensed Matter and Materials Physics 2013 Vol. 88 No. 5 P. 054505-1-054505-10

We investigate the effect of interacting quantum phase slips on persistent current and its fluctuations in ultrathin superconducting nanowires and nanorings pierced by the external magnetic flux. We derive the effective action for these systems and map the original problem onto an effective sine-Gordon theory on torus. We evaluate both the flux dependent persistent current ...

Added: February 9, 2015

Окубо Ю. undefined., Journal of Physics: Conference Series 2017 Vol. 804 No. 012036 P. 1-8

We investigate the existence and the orthogonality of the generalized Jack symmetric functions which play an important role in the AGT relations. We show their orthogonality by deforming them to the generalized Macdonald symmetric functions. ...

Added: October 26, 2017

Pelinovsky E., Kurkin A. A., A Kozelkov et al., European Journal of Mechanics - B/Fluids 2018 Vol. 72 P. 616-623

The paper presents results of numerical simulations of freely rising solid spheres in a viscous fluid. The
diameter of spheres was 5 mm, 7 mm, 10 mm, and 20 mm, and the corresponding Reynolds numbers
varies in the interval 1400 < Re < 10100. It has been found that the free rise path varies, as the
Galileo number ...

Added: October 21, 2018

М.: ИКИ РАН, 2011

Added: March 26, 2013

Musaev E., D. S. Berman, D. C. Thompson, Journal of High Energy Physics 2012 Vol. 1210

The reduction of the duality invariant approach to M-theory by a U-duality group valued
Scherk-Schwarz twist is considered. We show that all gaugings of SUGRA can be obtained
by dimensional reduction of the extended space. ...

Added: October 20, 2014

Semenov-Tian-Shansky K. M., М.В. Поляков, А.О. Смирнов et al., Теоретическая и математическая физика 2019 Т. 200 № 2 С. 290-309

Leading logarithms in massless nonrenormalizable effective field theories can be computed using nonlinear
recurrence relations. These recurrence relations follow from the fundamental requirements of unitarity,
analyticity, and crossing symmetry of scattering amplitudes and generalize the renormalization group
technique to the case of nonrenormalizable effective field theories. We review the existing exact solutions
of nonlinear recurrence relations relevant for field ...

Added: September 29, 2020

Zhuzhoma E. V., Medvedev V., Н.В. Исаенкова, Нелинейная динамика 2017 Т. 13 № 3 С. 399-412

В статье, используя методы теории динамических систем Морса–Смейла, авторы рассматривают топологическую структуру для точечно-зарядной модели магнитного поля областей фотосферы. Для произвольного количества зарядов (безотносительно к их местоположению) и не предполагая потенциальности поля <span data-mathml="B⃗ (следовательно, не используя конкретных формул), авторы приводят оценки, связывающие количества зарядов определенного типа с количеством нуль-точек. Для граничных оценок описывается топологическая структура магнитного ...

Added: October 12, 2017

Akhmedov E., E.T. Musaev, Physical Review D - Particles, Fields, Gravitation and Cosmology 2010 Vol. 81 P. 085010

We show that Polchinski equations in the D-dimensional matrix scalar field theory can be reduced at large N to the Hamiltonian equations in a (D+1)-dimensional theory. In the subsector of the Trϕl (for all l) operators we find the exact form of the corresponding Hamiltonian. The relation to the holographic renormalization group is discussed. ...

Added: February 27, 2013

Budkov Y., A.L. Kolesnikov, Polymer Science - Series C 2018 Vol. 60 No. Supplement 1 P. 148-159

Theoretical models of the conformational behavior of flexible polymer chains in mixed solvents enunciated in the world literature during the last decade are critically reviewed. Models describing different mechanisms of coil-to-globule transitions in a good solvent induced by cosolvent addition are highlighted. Special attention is given to the analysis of theoretical approaches to describing the ...

Added: November 30, 2018

Bodrova A., Alexander Osinsky, Nikolai V. Brilliantov, Scientific Reports 2020 Vol. 10 Article 693

We study analytically and numerically the distribution of granular temperatures in granular mixtures for
different dissipation mechanisms of inelastic inter-particle collisions. Both driven and force-free systems
are analyzed. We demonstrate that the simplified model of a constant restitution coefficient fails to
predict even qualitatively a granular temperature distribution in a homogeneous cooling state. At the
same time we reveal ...

Added: February 25, 2020

Min Namkung, Kwon Younghun, Scientific Reports 2018 Vol. 8 No. 1 P. 16915-1-16915-18

Sequential state discrimination is a strategy for quantum state discrimination of a sender’s quantum
states when N receivers are separately located. In this report, we propose optical designs that can
perform sequential state discrimination of two coherent states. For this purpose, we consider not
only binary phase-shifting-key (BPSK) signals but also general coherent states, with arbitrary prior
probabilities. Since ...

Added: November 16, 2020

Семин С. В., Kurkina O. E., Kurkin A. A. et al., Труды НГТУ им. Р.Е. Алексеева 2012 № 2(95) С. 48-65

Purpose: Numerical modeling of internal baroclinic disturbances of different shapes in a model lake with variable depth, analysis of velocity field of wave-induced current, especially in the near-bed layer.
Approach: The study is carried out with the use of numerical full nonlinear nonhydrostatic model for stratified fluid.
Findings: The full nonlinear numerical modeling of internal wave dynamics ...

Added: October 6, 2012