Article
Optics
Ming-Song Ding, Xuan-Xuan Xin, Si-Yu Qin, Chong Li
Summary: This study shows that bipartite entanglement and magnon-phonon steering in a PT-symmetry system are significantly enhanced compared to a conventional cavity magnomechanical system. Additionally, one-way-like magnon-phonon quantum steering can be achieved in the unbroken-PT-symmetry regime. The gain-loss system is demonstrated to be more stable than the conventional loss-loss system under certain parameters, providing potential applications in quantum state engineering and quantum information.
OPTICS COMMUNICATIONS
(2021)
Article
Quantum Science & Technology
Federico Roccati, Salvatore Lorenzo, G. Massimo Palma, Gabriel T. Landi, Matteo Brunelli, Francesco Ciccarello
Summary: In a paradigmatic setup, researchers studied the dynamics of correlations to observe PT-symmetric physics, finding that quantum correlations exhibit different long-time behaviors in the PT-broken phase and at the exceptional points. At the exceptional point, classical correlations diverge while quantum correlations tend to zero.
QUANTUM SCIENCE AND TECHNOLOGY
(2021)
Article
Optics
H. S. Karthik, H. Akshata Shenoy, A. R. Usha Devi
Summary: The Leggett-Garg inequality explores the macrorealistic limit in the quantum domain, and it has been shown that in N>2 quantum systems, the three-term inequality can be violated beyond the TTB 3/2 through suitable measurement schemes and state-update rules.
Article
Physics, Multidisciplinary
J. Ramya Parkavi, R. Muthuganesan, V. K. Chandrasekar, M. Lakshmanan
Summary: In this article, the properties of the Heisenberg XY model with and without PT-symmetric operation are explored using different measures of quantumness. In the absence of PT-symmetry, measures of entanglement and measurement-induced nonlocality (MIN) are found to be significant in detecting the quantumness of the model. It is observed that quantum correlations and teleportation fidelity decrease with temperature, but the intervention of PT-symmetric operation enhances quantum correlations. The results highlight the role of system parameters and PT-symmetric operation in quantum state teleportation.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2023)
Article
Nanoscience & Nanotechnology
Tom A. W. Wolterink, Matthias Heinrich, Stefan Scheel, Alexander Szameit
Summary: This research experimentally verifies the invariant behavior of two-photon behavior under the reversal of order for concatenated two-mode linear optical transformations in photonic quantum networks. The results indicate new ways in which quantum correlations may be preserved in counterintuitive ways, even in small-scale non-Hermitian networks.
Article
Quantum Science & Technology
Gang Yang, Yan-Xia Huang, Shi Rao
Summary: In this study, we investigate quantum steering and quantum entanglement in a hybrid cavity optomechanical system. It is found that by adjusting the system parameters, the direction of quantum steering can be altered, and it is possible to achieve quantum entanglement at higher temperature.
QUANTUM INFORMATION PROCESSING
(2023)
Article
Quantum Science & Technology
Si-Yu Guan, Hong-Fu Wang, Xuexi Yi
Summary: We propose a method to generate and control strong entanglement between photon and magnon modes by utilizing the cooperative effect of coherent coupling and dissipative coupling. This cooperative effect leads to the appearance of two exceptional points (EPs), where particularly obvious quantum entanglement and perfect one-way steering can be achieved.
NPJ QUANTUM INFORMATION
(2022)
Article
Quantum Science & Technology
Ting-Ting Dong, Nan Wang, Shi-Yan Li, Ai-Dong Zhu, Da-Wei Zhang
Summary: This study proposes a method to enhance entanglement and control EPR steering via dissipative coupling in an open cavity magnomechanical system. The results show that by adjusting the strength and relative phase of the dissipative coupling, the tripartite entanglement can be significantly enhanced and the steering directivity can be controlled.
ADVANCED QUANTUM TECHNOLOGIES
(2023)
Article
Optics
Alexander Poshakinskiy, Ivan Iorsh, Alexander Poddubny
Summary: In this theoretical study, we investigated the interaction between two vibrating quantum emitters and propagating photons near a one-dimensional waveguide. We found that strong optomechanical interaction can lead to the formation of spatially localized multiphonon modes, exhibiting parity-time (PT) symmetry breaking. These localized multiphonon states were interpreted by analyzing the energy spectrum in the quasiclassical approximation.
Article
Physics, Multidisciplinary
Jonas F. G. Santos, Fabricio S. Luiz
Summary: The study explores quantum thermodynamics aspects of a quantum harmonic oscillator under the framework of non-Hermitian quantum mechanics. By controlling the PT-symmetric features of the thermal reservoir, it is possible to reverse heat flow and reduce entropy production, leading to potential improvements in quantum thermodynamics protocols such as coherence protection and entropy reduction. By using thermal reservoirs based on PT-symmetric Hamiltonians, the modified quantum Otto cycle configuration can be altered from engine to refrigerator by varying the PT-symmetric parameter.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2021)
Article
Optics
Yu-Wei Lu, Jing-Feng Liu, Runhua Li, Haishu Tan, Yongyao Li
Summary: The Fano effect between two dissipation channels in the radiation continuum can be used to tune photon statistics. This article presents an analytical description of Fano-enhanced photon correlations based on cavity quantum electrodynamics, showing that the Fano effect can greatly improve the degree of antibunching. The study finds that the enhancement factors and optimal conditions are related to the Fano parameter q, and the Fano enhancement is robust against decoherence processes and can survive in the weak coupling regime. This work provides insights into tuning photon statistics through the Fano effect, offering a new approach to enhance photon correlations and generate nonclassical light in various systems without strong light-matter interaction.
Article
Optics
P. Ornelas-Cruces, L. Rosales-Zarate
Summary: Nonlocal quantum correlations are important for potential applications in quantum optics and quantum information. This study investigates the regions where bipartite and tripartite steering can be generated by analyzing the Hamiltonian of a triple photon parametric down-conversion process.
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
(2023)
Article
Quantum Science & Technology
Nan Wang, Zhi-Bo Yang, Shi-Yan Li, Ting-Ting Dong, Ai-Dong Zhu
Summary: In this study, quantum steering between two magnon modes in a cavity-magnonics system is investigated by applying a two-photon drive field to the microwave cavity. The entangled magnon modes can exhibit one-way steering when four-wave mixing occurs. The direction of quantum steering is determined by the mode populations.
EPJ QUANTUM TECHNOLOGY
(2023)
Article
Astronomy & Astrophysics
Mikhail Pavlov
Summary: In this article, we examine a specific instance of the 4-pt non-vacuum classical block associated with the W3 algebra. We establish the monodromy problem for the block and derive the monodromy equations in the heavy-light approximation. By utilizing the parameters of the 4-pt vacuum W3 block to fix the remaining functional arbitrariness, we calculate the 4-pt non-vacuum W3 block function.
Article
Optics
Sebastian Schiffer, Xia-Ji Liu, Hui Hu, Jia Wang
Summary: We studied a generalized Aubry-Andre model that follows PT symmetry, and found a robust PT-symmetric phase that can support an Anderson localization transition. The model provides a perfect platform for studying disorder-driven localization phenomena in a PT-symmetric system.
Article
Optics
Joanna K. Kalaga, Anna Kowalewska-Kudlaszyk, Mateusz Nowotarski, Wieslaw Leonski
Summary: We investigated the time correlations of a quantum nonlinear Kerr-like oscillator pumped by ultrashort coherent pulses, analyzing the violation of the Leggett-Garg inequality. We observed how these correlations change as the system's dynamics transition between regular and chaotic regions in its classical counterpart.
Article
Multidisciplinary Sciences
Vinh Le Duc, Mateusz Nowotarski, Joanna K. Kalaga
Summary: This study investigates a PT-symmetric system involving three optical resonant elements and explores the quantum correlations between subsystems. The correlations strongly rely on the parameters describing the interaction between subsystems and the energy gain and loss in the active and passive elements. The study estimates the range of interaction parameter values for generating the strongest entanglement and demonstrates that the system can serve as a source of stable entangled states.
Article
Physics, Applied
M. Kostrzewa, A. P. Durajski, J. K. Kalaga, R. Szczesniak
Summary: The thermodynamical properties of the superconducting state in metallic hydrogen were determined based on the model of two compressed hydrogen planes, considering electronic correlations and non-conventional electron-phonon coupling functions. The critical temperature values are significantly affected by the inclusion or omission of certain factors, while other thermodynamic quantities align closely with predictions from the BCS theory.
JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM
(2021)
Article
Mathematics, Applied
I. A. Domagalska, M. W. Jarosik, A. P. Durajski, J. K. Kalaga, R. Szczesniak
Summary: This study analysed the dynamics of positively charged ions in diatomic molecules and found that chaotic dynamics of cores induced chaotic evolution of electronic Hamiltonian parameters. Changes in cation masses or charge arrangement did not qualitatively affect Lyapunov exponents in the A-Omega parameter space.
PHYSICA D-NONLINEAR PHENOMENA
(2021)
Article
Medicine, General & Internal
Lukasz Jerzy Janicki, Wieslaw Leonski, Jerzy Stanislaw Janicki, Mateusz Nowotarski, Miroslaw Dziuk, Ryszard Piotrowicz
Summary: The study demonstrates that the use of SATRO ECG software, in combination with resting and stress ECG, can effectively predict significant perfusion abnormalities during exercise. This has important implications for the early diagnosis of ischemic heart disease.
Article
Physics, Multidisciplinary
Joanna K. Kalaga, Wieslaw Leonski, Radoslaw Szczesniak, Jan Perina
Summary: We investigate the relationship between the states of three-qubit systems and linear entropy, as well as measures of coherence such as degree of coherence, first- and second-order correlation functions. We demonstrate that qubit-qubit states exhibit strong entanglement when the linear entropy falls within a certain range of values. Additionally, we derive the conditions for the boundary values of linear entropy, which are parameterized by measures of coherence.
Article
Nanoscience & Nanotechnology
I. A. Domagalska, A. P. Durajski, K. M. Gruszka, I. A. Wrona, K. A. Krok, W. Leonski, R. Szczesniak
Summary: In this study, the energy levels of hydrogen bridges in nanojunctions with platinum, gold, or copper anchors were investigated. It was found that a strong electron flow can reduce the number of allowed energy levels in the bridge, leading to the disappearance of states with the highest energy. This effect is related to the PT symmetry breaking of the electronic Hamiltonian of the bridge.
APPLIED NANOSCIENCE
(2022)
Article
Physics, Multidisciplinary
A. Szewczyk, W. Leonski, R. Szczesniak
Summary: This study investigates the influence of PT-symmetry breaking on the chaotic properties of coupled magnetic pendulums. The PT-symmetric system is described using classical approach with coupled second-order nonlinear differential equations. By using the damping coefficient A as the control parameter for PT-symmetry and evaluating the two-dimensional basin plot of the pendulum's motion, the fractal of measure for unbroken PT-symmetry is calculated to be approximately 2, while it changes to approximately 1.25 for broken symmetry.
ACTA PHYSICA POLONICA A
(2022)
Article
Physics, Multidisciplinary
V Le Duc, J. K. Kalaga, W. Leonski
Summary: The study focuses on a system of two linearly interacting Kerr-like nonlinear oscillators, initially in a coherent state. The system's dynamics and mutual correlations of the field were discussed, using normalized first- and second-order coherence functions as measures. Analytical formulas for these functions were derived, showing a strong dependence on the linear coupling parameter for their time evolution.
ACTA PHYSICA POLONICA A
(2021)
Article
Physics, Multidisciplinary
M. Nowotarski, J. K. Kalaga
Summary: This study applies the tools of quantifying Bell nonlocality and ICPS symmetric states to photon-number entangled states in Kerr media, using projections and negativity calculations to explore the lower bound of entanglement and nonlocality in the physical system.
ACTA PHYSICA POLONICA A
(2021)