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

• 来源期刊: 中国物理B（英文版）
• 关键词: quantum speed limit time quantum feedback control speedup
• 年，卷（期）: 2018,（1）
• 页码范围: 253-257
• 页数: 5页
• 语种: 英文
• DOI: 10.1088/1674-1056/27/1/010303

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.