中国物理B ›› 2018, Vol. 27 ›› Issue (1): 10303-010303.doi: 10.1088/1674-1056/27/1/010303

• SPECIAL TOPIC—Non-equilibrium phenomena in soft matters • 上一篇    下一篇

Quantum speed limit time of a two-level atom under different quantum feedback control

Min Yu(余敏), Mao-Fa Fang(方卯发), Hong-Mei Zou(邹红梅)   

  1. Department of Physics, Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, and Synergetic Innovation Center for Quantum Effects and Applications, Hunan Normal University, Changsha 410081, China
  • 收稿日期:2017-08-16 修回日期:2017-09-27 出版日期:2018-01-05 发布日期:2018-01-05
  • 通讯作者: Mao-Fa Fang E-mail:mffang@hunnu.edu.cn
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant No. 11374096), Hunan Provincial Innovation Foundation for Postgraduate, China (Grant No. CX2017B177), and the Scientific Research Project of Hunan Provincial Education Department, China (Grant No. 16C0949).

Quantum speed limit time of a two-level atom under different quantum feedback control

Min Yu(余敏), Mao-Fa Fang(方卯发), Hong-Mei Zou(邹红梅)   

  1. Department of Physics, Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, and Synergetic Innovation Center for Quantum Effects and Applications, Hunan Normal University, Changsha 410081, China
  • Received:2017-08-16 Revised:2017-09-27 Online:2018-01-05 Published:2018-01-05
  • Contact: Mao-Fa Fang E-mail:mffang@hunnu.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant No. 11374096), Hunan Provincial Innovation Foundation for Postgraduate, China (Grant No. CX2017B177), and the Scientific Research Project of Hunan Provincial Education Department, China (Grant No. 16C0949).

摘要:

We investigate the quantum speed limit time (QSLT) of a two-level atom under quantum-jump-based feedback control or homodyne-based feedback control. Our results show that the two different feedback control schemes have different influences on the evolutionary speed. By adjusting the feedback parameters, the quantum-jump-based feedback control can induce speedup of the atomic evolution from an excited state, but the homodyne-based feedback control cannot change the evolutionary speed. Additionally, the QSLT for the whole dynamical process is explored. Under the quantum-jump-based feedback control, the QSLT displays oscillatory behaviors, which implies multiple speed-up and speed-down processes during the evolution. While, the homodyne-based feedback control can accelerate the speed-up process and improve the uniform speed in the uniform evolution process.

关键词: quantum speed limit time, quantum feedback control, speedup

Abstract:

We investigate the quantum speed limit time (QSLT) of a two-level atom under quantum-jump-based feedback control or homodyne-based feedback control. Our results show that the two different feedback control schemes have different influences on the evolutionary speed. By adjusting the feedback parameters, the quantum-jump-based feedback control can induce speedup of the atomic evolution from an excited state, but the homodyne-based feedback control cannot change the evolutionary speed. Additionally, the QSLT for the whole dynamical process is explored. Under the quantum-jump-based feedback control, the QSLT displays oscillatory behaviors, which implies multiple speed-up and speed-down processes during the evolution. While, the homodyne-based feedback control can accelerate the speed-up process and improve the uniform speed in the uniform evolution process.

Key words: quantum speed limit time, quantum feedback control, speedup

中图分类号:  (Decoherence; open systems; quantum statistical methods)

  • 03.65.Yz
03.67.Lx (Quantum computation architectures and implementations) 42.50.-p (Quantum optics)