Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Laser Physics Letters

Geometric phase of an atomic qubit coupled to a Lorentzian reservoir

Mingfeng Chen, Rongxin Chen, Zhen‐Biao Yang

Published Feb 7, 2017• 1 citation
Publisher

Abstract

Abstract We calculate the geometric phase for an atomic qubit coupled to a zero-temperature bosonic reservoir with a Lorentzian spectral density. The geometric phase is obtained without tracing out the degrees of freedom of the reservoir. It is shown that the phase accumulated by the total system is purely geometric and exhibits an oscillation behaviour in both the Markovian and non-Markovian regimes.

DOI
10.1088/1612-202x/aa5a9a

Related papers

Non-Markovian dynamics of the mixed-state geometric phase of dissipative qubits

Wei Guo, Jian Ma, Xiaolei Yin +2 more

We investigate the geometric phase of a two-level atom (qubit) coupled to a bosonic reservoir with Lorentzian spectral density and find that for the non-Markovian dynamics in which the rotating-wave approximation (RWA) is performed, the geometric phase has a $\ensuremath{\pi}$-phase jump at the nodal point. However, the exact result without the RWA given by the hierarchical equations of motion method shows that there is no such phase jump or nodal structure in the geometric phase. Thus our results demonstrate that the counterrotating terms significantly contribute to the geometric phase in the multimode Hamiltonian under certain circumstances.

arXiv:1412.5412•Physical Review A•Dec 29, 2014•9 citations

Non-Markovian effect on the geometric phase of a dissipative qubit

Juanjuan Chen, Jun‐Hong An, Qingjun Tong +2 more

We studied the geometric phase of a two-level atom coupled to an environment with Lorentzian spectral density. The non-Markovian effect on the geometric phase is explored analytically and numerically. In the weak coupling limit, the lowest order correction to the geometric phase is derived analytically and the general case is calculated numerically. It was found that the correction to the geometric phase is significantly large if the spectral width is small, and in this case the non-Markovian dynamics has a significant impact on the geometric phase. When the spectral width increases, the correction to the geometric phase becomes negligible, which shows the robustness of the geometric phase to the environmental white noises. The result is significant to the quantum information processing based on the geometric phase.

arXiv:1001.3454•Physical Review A•Feb 24, 2010•38 citations

Characterization of non-Markovianity with maximal extractable qubit-reservoir entanglement

Zhen‐Biao Yang, Pei‐Rong Han, Fan Wu +5 more

Abstract Understanding the dynamical behavior of a qubit in a reservoir is critical to applications in quantum technological protocols, ranging from quantum computation to quantum metrology. The effect of the reservoir depends on reservoir’s spectral structure, as well as on the qubit-reservoir coupling strength. We here propose a measure for quantifying the non-Markovian effect of a reservoir with a Lorentzian spectrum, based on the maximum qubit-reservoir quantum entanglement that can be extracted. Numerical simulation shows this entanglement exhibits a monotonous behavior in response to the variation of the coupling strength. We confirm the validity of this measure with an experiment, where a superconducting qubit is controllably coupled to a lossy resonator, which acts as a reservoir for the qubit. The experimental results illustrate the maximal extractable entanglement is progressively increased with the strengthening of the non-Markovianity.

•Apr 18, 2024•0 citations

Markovian and non-Markovian effects on the geometric phase of a dissipative Josephson qubit

Zhiyuan Chen, Liping Guo, Fengfeng Luo

Geometric phases are investigated for a Josephson qubit interacting with the Markovian and non-Markovian environments at arbitrary temperature according to a kinematic approach. In order to obtain the condition allowing experimental observation of geometric phase, we also estimate the decoherence times. The result shows that the Aharonov-Anandan phase may be different from the Berry phase under the environment perturbations. By comparing with the numerical result of the geometric phase as a function of the initial angle, we find that at low temperature, the effect of Markovian environment is larger than the non-Markovian one on the geometric phase. An approach is proposed to understand the accumulative effects of the geometric phase and its robustness to high-frequency noise, which may be helpful for geometric quantum information processing.

Europhysics Letters (EPL)•Nov 1, 2011•7 citations

Proposed method for direct measurement of the non-Markovian character of the qubits coupled to bosonic reservoirs

Z. Y. Xu, W. L. Yang, Mang Feng

Non-Markovianity is a recently proposed characterization of the non-Markovian behavior in an open quantum system, based on which we first present a practical idea for directly measuring the non-Markovian character of a single qubit coupled to a zero-temperature bosonic reservoir, and then extend to investigate the dynamics of two noninteracting qubits subject to two reservoirs, respectively, with a lower bound of non-Markovianity. Our scheme, with no need for optimization procedures and quantum state tomography, is helpful for experimental implementation.

arXiv:0912.2879•Physical Review A•Apr 16, 2010•72 citations

Characterization of non-Markovianity with maximal extractable qubit-reservoir entanglement

Pei‐Rong Han, Fan Wu, Xin-Jie Huang +5 more

Understanding the dynamical behavior of a qubit in a reservoir is critical to applications in quantum technological protocols, ranging from quantum computation to quantum metrology. The effect of the reservoir depends on the reservoir's spectral structure as well as on the qubit-reservoir coupling strength. We here propose a measure for quantifying the non-Markovian effect of a reservoir with a Lorentzian spectrum, based on the maximum qubit-reservoir quantum entanglement that can be extracted. Numerical simulation shows that this entanglement exhibits a monotonous behavior in response to the variation of the coupling strength. We confirm the validity of this measure with an experiment where a superconducting qubit is controllably coupled to a lossy resonator, which acts as a reservoir for the qubit. The experimental results illustrate that the maximal extractable entanglement is progressively increased with the strengthening of non-Markovianity.

arXiv:2403.01967•Applied Physics Letters•Sep 16, 2024•3 citations
Abstract We calculate the geometric phase for an atomic qubit coupled to a zero-temperature bosonic reservoir with a Lorentzian spectral density. The geometric phase is obtained without tracing out the degrees of freedom of the reservoir. It is shown that the phase accumulated by the total system is purely geometric and exhibits an oscillation behaviour in both the Markovian and non-Markovian regimes.
We investigate the geometric phase of a two-level atom (qubit) coupled to a bosonic reservoir with Lorentzian spectral density and find that for the non-Markovian dynamics in which the rotating-wave approximation (RWA) is performed, the geometric phase has a $\ensuremath{\pi}$-phase jump at the nodal point. However, the exact result without the RWA given by the hierarchical equations of motion method shows that there is no such phase jump or nodal structure in the geometric phase. Thus our results demonstrate that the counterrotating terms significantly contribute to the geometric phase in the multimode Hamiltonian under certain circumstances.
We studied the geometric phase of a two-level atom coupled to an environment with Lorentzian spectral density. The non-Markovian effect on the geometric phase is explored analytically and numerically. In the weak coupling limit, the lowest order correction to the geometric phase is derived analytically and the general case is calculated numerically. It was found that the correction to the geometric phase is significantly large if the spectral width is small, and in this case the non-Markovian dynamics has a significant impact on the geometric phase. When the spectral width increases, the correction to the geometric phase becomes negligible, which shows the robustness of the geometric phase to the environmental white noises. The result is significant to the quantum information processing based on the geometric phase.
Abstract Understanding the dynamical behavior of a qubit in a reservoir is critical to applications in quantum technological protocols, ranging from quantum computation to quantum metrology. The effect of the reservoir depends on reservoir’s spectral structure, as well as on the qubit-reservoir coupling strength. We here propose a measure for quantifying the non-Markovian effect of a reservoir with a Lorentzian spectrum, based on the maximum qubit-reservoir quantum entanglement that can be extracted. Numerical simulation shows this entanglement exhibits a monotonous behavior in response to the variation of the coupling strength. We confirm the validity of this measure with an experiment, where a superconducting qubit is controllably coupled to a lossy resonator, which acts as a reservoir for the qubit. The experimental results illustrate the maximal extractable entanglement is progressively increased with the strengthening of the non-Markovianity.
Geometric phases are investigated for a Josephson qubit interacting with the Markovian and non-Markovian environments at arbitrary temperature according to a kinematic approach. In order to obtain the condition allowing experimental observation of geometric phase, we also estimate the decoherence times. The result shows that the Aharonov-Anandan phase may be different from the Berry phase under the environment perturbations. By comparing with the numerical result of the geometric phase as a function of the initial angle, we find that at low temperature, the effect of Markovian environment is larger than the non-Markovian one on the geometric phase. An approach is proposed to understand the accumulative effects of the geometric phase and its robustness to high-frequency noise, which may be helpful for geometric quantum information processing.
Non-Markovianity is a recently proposed characterization of the non-Markovian behavior in an open quantum system, based on which we first present a practical idea for directly measuring the non-Markovian character of a single qubit coupled to a zero-temperature bosonic reservoir, and then extend to investigate the dynamics of two noninteracting qubits subject to two reservoirs, respectively, with a lower bound of non-Markovianity. Our scheme, with no need for optimization procedures and quantum state tomography, is helpful for experimental implementation.
Understanding the dynamical behavior of a qubit in a reservoir is critical to applications in quantum technological protocols, ranging from quantum computation to quantum metrology. The effect of the reservoir depends on the reservoir's spectral structure as well as on the qubit-reservoir coupling strength. We here propose a measure for quantifying the non-Markovian effect of a reservoir with a Lorentzian spectrum, based on the maximum qubit-reservoir quantum entanglement that can be extracted. Numerical simulation shows that this entanglement exhibits a monotonous behavior in response to the variation of the coupling strength. We confirm the validity of this measure with an experiment where a superconducting qubit is controllably coupled to a lossy resonator, which acts as a reservoir for the qubit. The experimental results illustrate that the maximal extractable entanglement is progressively increased with the strengthening of non-Markovianity.