Article
Optics
Ana Laura Gramajo, Daniel Dominguez, Maria Jose Sanchez
Summary: We report on a mechanism that optimizes the generation of steady-state entanglement in a system of coupled qubits driven by microwave fields. By tuning the qubit-reservoir couplings and driving protocol, a maximally entangled state can be achieved without the need for fine tuning of multiphoton resonances. The results show that the steady-state concurrence of the two qubits can approach values close to 1 in a wide range of driving amplitudes.
Article
Physics, Multidisciplinary
Xiao-Ming Li, Zhong-Xiao Man, Yun-Jie Xia
Summary: This study focuses on improving the steady-state coherence and entanglement of two coupled qubits by adjusting the parallel components of the system-reservoir interaction Hamiltonian. It shows that in the non-equilibrium case, increasing the parallel components can significantly enhance the coherence and entanglement between the qubits. However, in the equilibrium situation, these components do not affect the coherence and entanglement.
Article
Physics, Fluids & Plasmas
Yi-jia Yang, Yu-qiang Liu, Chang-shui Yu
Summary: A quantum thermal diode is designed using three pairwise coupled qubits, with two connected to a common reservoir and the other to an independent reservoir. It is found that internal couplings between qubits can enhance heat currents. The steady state of the system is dependent on the initial state, but the rectification factor is independent of it. Classical correlation plays a vital role in the system, while quantum entanglement and quantum discord are absent in the steady state.
Article
Physics, Multidisciplinary
Yang-Qing Guo, Ping-Xing Chen, Jian Li
Summary: Quantum entanglement, a crucial resource in quantum information processing, diminishes when the quantum system interacts with its noisy environment. Therefore, it is important to study the dynamic properties of entanglement in open quantum systems. This study focuses on two qubits coupled to an adjustable environment, specifically a semi-infinite transmission line. By adjusting the qubits' transition frequencies, the relaxation processes of the two qubits can be modified through individual channels or a collective channel or both. The entanglement dynamics in this model system with an initial Werner state is examined, and the phenomena of entanglement sudden death and revival are observed. To overcome the difficulties of preparing Werner states experimentally, a new type of entangled state called a pseudo-Werner state is introduced, which retains similar entangling properties as the Werner state and is more experimentally feasible. Detailed procedures for generating the pseudo-Werner state and studying entanglement dynamics with it are provided, which can be implemented straightforwardly in a superconducting waveguide quantum electrodynamics system.
Article
Optics
V. O. Munyaev, M. Bastrakova
Summary: The quantum level population behavior of two coupled flux qubits depending on the external driving field characteristics is studied in this research. Explicit expressions for the multiphoton transition probabilities at an arbitrary control field amplitude are obtained for the case of small tunnel splitting energies. It is found that the positions of multiphoton resonances are stable to dissipative processes through the use of the Floquet-Markov equation.
News Item
Optics
Hyunseok Jeong
Summary: A scheme for converting qubits between discrete and continuous variables opens up possibilities for more efficient quantum networks.
Article
Materials Science, Multidisciplinary
A-B A. Mohamed, A-H Abdel-Aty, H. Eleuch
Summary: This paper investigates the influence of intrinsic decoherence on the quantum memory and coherence dynamics of two dipole-coupled qubits in a non-degenerate bimodal cavity. The results show that the nonlinear interactions between the qubits and the cavity generate quantum-memory-assisted entropic uncertainty, mixedness, and entanglement, which depend not only on the qubit-qubit interaction but also on the intrinsic decoherence and coherence intensity of the initial two-mode cavity states.
RESULTS IN PHYSICS
(2022)
Article
Optics
Huiping Zhan, Huatang Tan
Summary: This paper investigates a scheme for achieving long-time sustainable Bell states of two distant qubits mediated by a one-dimensional waveguide. The scheme utilizes time-continuous photon counting or homodyne detection. Different Bell states can be obtained in the long-time regime, and the physical reasons behind them are analyzed. The scheme is advantageous for generating stable Bell states compared to previous studies.
Article
Optics
Vladimir M. Stojanovie, Julian K. Nauth
Summary: This paper focuses on the engineering of the two-excitation Dicke state ID32) in a three-qubit system with all-to-all Ising-type qubit-qubit interaction and global transverse control fields. A pulse sequence is proposed, consisting of three instantaneous control pulses and two finite-duration Ising-interaction pulses, based on the concept of the symmetric sector. Numerical analysis is conducted to demonstrate the robustness of the proposed state-preparation scheme to systematic errors. The generalization of this scheme to systems with N > 4 qubits is also discussed.
Article
Physics, Multidisciplinary
Y. Khlifi, S. Seddik, A. El Allati
Summary: The entangled steady-state behavior between two quantum thermal refrigeration machines is evaluated and it is found that the steady-state entanglement is more robust in the case of resonance. The effect of temperature on entanglement is also studied.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2022)
Article
Quantum Science & Technology
Yabo Zhao, Ruiqing Zhao, Lanxin Chen, Jingyu Pan, Mei Zhang
Summary: This paper investigates the steady-state entanglement in a mechanically coupled double cavity with levitating rigid magnetic spheres. Numerical simulations and calculations show that steady-state entanglement can form between various components of the system and is robust against ambient temperature.
QUANTUM INFORMATION PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Caspar Hopfmann, Nand Lal Sharma, Weijie Nie, Robert Keil, Fei Ding, Oliver G. Schmidt
Summary: The study on heralded spin preparation using excited state resonances of GaAs quantum dots revealed properties of different quantum dot energy levels, simplified determination of spin preparation fidelities, and found high spin preparation fidelities and short decay times.
Article
Optics
Mingjian He, Robert Malaney, Ryan Aguinaldo
Summary: In this paper, a nondeterministic teleportation protocol combining a Gaussian CV resource state with a modified Bell state measurement is presented, which significantly improves the fidelity of DV-qubits over a wide range of channel losses. Furthermore, the use of non-Gaussian operations on the CV resource state is shown to achieve near unity fidelity for any channel loss.
Article
Physics, Multidisciplinary
G. L. Decordi, A. Vidiella-Barranco
Summary: In this work, we explore the impact of a minimal, phase-sensitive environment on a pair of coupled qubits. The environment consists of a single-mode field prepared initially in a Schrodinger cat state, which is a quantum superposition of two squeezed coherent states. We provide an analytical solution to the model and investigate the degradation of the quantum properties of the system caused by the environment. Specifically, we find that the time-averaged linear entropy for long times, (S) over bar (T), has a linear dependence on both Mandel's Q parameter and the variance of the (X) over cap quadrature of the initial state of the environment.
Article
Optics
J. Nogueira, P. A. Oliveira, F. M. Souza, L. Sanz
Summary: This paper presents a proof of principle for generating pure maximally entangled states from the GHZ class in the experimental context of charged quantum dots. The study investigates the interplay between coherent tunneling events and many-body interactions, and evaluates the physical requirements and challenges for dynamically generating GHZ states in an N-qubit scenario.
Correction
Physics, Multidisciplinary
E. del Valle, A. Gonzalez-Tudela, F. P. Laussy, C. Tejedor, M. J. Hartmann
PHYSICAL REVIEW LETTERS
(2016)
Article
Physics, Mathematical
E. Zubizarreta Casalengua, J. C. Lopez Carreno, E. del Valle, F. P. Laussy
JOURNAL OF MATHEMATICAL PHYSICS
(2017)
Article
Optics
Juan Camilo Lopez Carreno, Elena del Valle, Fabrice P. Laussy
LASER & PHOTONICS REVIEWS
(2017)
Article
Optics
Carlos Sanchez Munoz, Fabrice P. Laussy, Elena del Valle, Carlos Tejedor, Alejandro Gonzalez-Tudela
Article
Multidisciplinary Sciences
Alvaro Cuevas, Juan Camilo Lopez Carreno, Blanca Silva, Milena De Giorgi, Daniel G. Suarez-Forero, Carlos Sanchez Munoz, Antonio Fieramosca, Filippo Cardano, Lorenzo Marrucci, Vittorianna Tasco, Giorgio Biasiol, Elena del Valle, Lorenzo Dominici, Dario Ballarini, Giuseppe Gigli, Paolo Mataloni, Fabrice P. Laussy, Fabio Sciarrino, Daniele Sanvitto
Article
Multidisciplinary Sciences
B. Silva, C. Sanchez Munoz, D. Ballarini, A. Gonzalez-Tudela, M. de Giorgi, G. Gigli, K. West, L. Pfeiffer, E. del Valle, D. Sanvitto, F. P. Laussy
SCIENTIFIC REPORTS
(2016)
Article
Multidisciplinary Sciences
Juan Camilo Lopez Carreno, Elena del Valle, Fabrice P. Laussy
SCIENTIFIC REPORTS
(2018)
Article
Optics
J. C. Lopez Carreno, E. Zubizarreta Casalengua, F. P. Laussy, E. del Valle
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
(2019)
Article
Physics, Multidisciplinary
C. A. Downing, J. C. Lopez Carreno, F. P. Laussy, E. del Valle, A. I. Fernandez-Dominguez
PHYSICAL REVIEW LETTERS
(2019)
Review
Optics
Eduardo Zubizarreta Casalengua, Juan Camilo Lopez Carreno, Fabrice P. Laussy, Elena del Valle
LASER & PHOTONICS REVIEWS
(2020)
Article
Optics
Juan Camilo Lopez Carreno, Eduardo Zubizarreta Casalengua, Blanca Silva, Elena del Valle, Fabrice P. Laussy
Summary: This article describes some of the main external mechanisms that lead to a loss of antibunching in quantum light, including contamination by noise, time jitter in photon detection, and the effect of frequency filtering. The formalism for describing time jitter is derived and connected to the existing formalism for frequency filtering. The emission from a two-level system under both incoherent and coherent driving is studied, with analytical solutions revealing unexpected structures in the transitions from perfect antibunching to thermal or uncorrelated emission.
Article
Optics
C. A. Downing, J. C. Lopez Carreno, A. Fernandez-Dominguez, E. del Valle
Article
Quantum Science & Technology
J. C. Lopez Carreno, E. Zubizarreta Casalengua, F. P. Laussy, E. del Valle
QUANTUM SCIENCE AND TECHNOLOGY
(2018)
Article
Optics
J. C. Lopez Carreno, C. Sanchez Munoz, E. del Valle, F. P. Laussy
Article
Optics
Eduardo Zubizarreta Casalengua, Juan Camilo Lopez Carreno, Fabrice P. Laussy, Elena del Valle
