Article
Quantum Science & Technology
Hong Liu, Shreya Vardhan
Summary: A universal approximation for Renyi entropies in a pure state at late times in a nonintegrable many-body system has been developed, which is independent of the details of the initial state and consistent with unitary time evolution. This approximation can be used to calculate entanglement entropies in gravity systems such as black holes, addressing the information loss paradox of Hawking, and providing a derivation of replica wormholes in recent models.
Article
Physics, Multidisciplinary
Timur Koyuk, Udo Seifert
Summary: This paper investigates the properties of the thermodynamic uncertainty relation (TUR) in complex systems with many degrees of freedom. By analyzing the entropy production of mixtures of driven particles, an explicit expression for the optimal estimate of total entropy production is derived and applied to driven lattice gases.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Alexander Poshakinskiy, Alexander N. Poddubny
Summary: In this study, we investigate subradiant states in an array of atoms coupled to photons propagating in a one-dimensional waveguide, focusing on the strongly interacting many-body regime with large excitation fill factor f. By introducing a generalized many-body entropy of entanglement and using exact numerical diagonalization followed by high-order singular value decomposition, we are able to visualize and understand the structure of a many-body quantum state. Our findings reveal the breakdown of fermionized subradiant states with the increase of f, the emergence of short-ranged dimerized antiferromagnetic correlations at the critical point f = 1/2, and the complete disappearance of subradiant states at f > 1/2.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Junghyun Kim, Woongki Na, Jonghyeon Kim, Pyeongjae Park, Kaixuan Zhang, Inho Hwang, Young-Woo Son, Jae Hoon Kim, Hyeonsik Cheong, Je-Geun Park
Summary: The unique properties of the magnetic exciton in NiPS3, which arises between two quantum many-body states, have been discovered. The exciton shows an exceedingly narrow photoluminescence spectral width of 0.4 meV. Doping experiments and theoretical studies reveal that the magnetic exciton is suppressed upon Cd doping, while the width of the exciton only gradually increases and the antiferromagnetic ground state remains stable. This research highlights the importance of lattice uniformity for the formation of coherent magnetic exciton.
Article
Quantum Science & Technology
Julian Muenzberg, Christoph Dittel, Maxime Lebugle, Andreas Buchleitner, Alexander Szameit, Gregor Weihs, Robert Keil
Summary: The study investigates how symmetries control the suppression of many-body output events in a four-photon interference experiment. It is found that totally destructive interference only requires mutual indistinguishability between symmetrically paired particles. The experiment's outcome aligns well with a quantitative simulation that considers higher-order emission of the photon source, imbalances in the scattering network, partial distinguishability, and photon loss.
Article
Physics, Multidisciplinary
Remi Lefevre, Krissia Zawadzki, Gregoire Ithier
Summary: In this work, a new approach is introduced to evaluate the many-body density of states (MBDoS) in the general case of non-interacting systems of identical quantum particles. The method utilizes the principal component analysis of a filling matrix to expand the many-body spectrum as a weighted sum of singular vectors of the filling matrix. The weighting coefficients only involve renormalized energies obtained from the single body spectrum. The effectiveness of this method is demonstrated in two classes of problems.
NEW JOURNAL OF PHYSICS
(2023)
Article
Physics, Fluids & Plasmas
Urbashi Satpathi, Sayak Ray, Amichay Vardi
Summary: We study the interplay of chaos and tunneling between two weakly coupled Bose-Josephson junctions. The classical phase space of the composite system has a mixed structure, including quasi-integrable self-trapping islands separated by a chaotic sea. We show that the chaos-enhanced many-body dynamical tunneling gap between macroscopic Schrodinger cat states supported by these islands. The many-body tunneling rate fluctuates over several orders of magnitude with small variations of the system parameters or the particle number.
Article
Physics, Fluids & Plasmas
Rueih-Sheng Fu, Todd R. Gingrich
Summary: This study explores TUR-like bounds in overdamped and underdamped Langevin dynamics using large deviation theory, offering a new perspective and approach. It is found that current fluctuations achieved by scaling time can provide a deeper understanding of the relationship between current and dissipation in non-equilibrium systems.
Article
Optics
Mladen Pavicic, Norman D. Megill
Summary: The development of quantum computation and communication requires a large supply of contextual sets. This study presents three methods for the automated generation of contextual sets in any dimension and successfully generates millions of new contextual sets in odd dimensions.
Article
Materials Science, Multidisciplinary
Ruoshui Wang, Timothy H. Hsieh, Guifre Vidal
Summary: In this study, we used matrix product techniques to investigate the performance of two algorithms for obtaining the ground state of a quantum many-body Hamiltonian in infinite systems. The first algorithm is a generalization of the quantum approximate optimization algorithm, which uses a quantum computer to evolve an initial product state into an approximation of the ground state by alternating between two Hamiltonians. The second algorithm is the variational imaginary time ansatz, which uses a classical computer to simulate the ground state via alternating imaginary time steps with two Hamiltonians.
Article
Quantum Science & Technology
Marko Ljubotina, Barbara Roos, Dmitry A. Abanin, Maksym Serbyn
Summary: This paper formulates an approach to control quantum systems based on matrix product states (MPSs). By comparing different methods applied to the PXP model and nonintegrable Ising model, it is found that the leakage-based approach performs better in controlling quantum many-body systems.
Article
Physics, Multidisciplinary
Markus Rademacher, Michael Konopik, Maxime Debiossac, David Grass, Eric Lutz, Nikolai Kiesel
Summary: This study verifies the validity of fluctuation theorems in the presence of simultaneous mechanical and thermal changes by implementing fast and controlled temperature variations using feedback cooling techniques.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Applied
Michal Kloc, Kurt Meier, Kimon Hadjikyriakos, Gernot Schaller
Summary: In this study, it is demonstrated that the lower levels of a large-spin network can act as a quantum-absorption refrigerator with a cooling current scaling quadratically with the number of spins. This scaling behavior is also observed for noise and entropy production rate.
PHYSICAL REVIEW APPLIED
(2021)
Article
Physics, Multidisciplinary
Jie Ren, Chenguang Liang, Chen Fang
Summary: In quantum systems, a subspace spanned by degenerate eigenvectors of the Hamiltonian may have higher symmetries than those of the Hamiltonian itself. Coupling an external field to certain generators of the quasisymmetry group can lift the degeneracy and result in exactly periodic dynamics within the degenerate subspace.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Fluids & Plasmas
Takaaki Monnai
Summary: This paper analytically demonstrates that the thermodynamic uncertainty relation (TUR) holds for the work performed on an externally perturbed quantum harmonic oscillator interacting with multiple reservoirs in full quantum regime. It evaluates how the noncommutativity affects the thermodynamic precision and explores its experimental accessibility.
