A new approach for open quantum systems based on a phonon number representation of a harmonic oscillator bath
A new approach for open quantum systems based on a phonon number representation of a harmonic oscillator bath
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DOI：
10.1016/j.aop.2019.168005
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发表时间：
2020-01-01
影响因子：
3
通讯作者：
Hagino, K.
中科院分区：
文献类型：
--
作者：
Tokieda, M.;Hagino, K.
为了研究与谐振子槽耦合的系统，我们提出了一种基于槽的声子数表示的新方法。与层次运动方程的方法相比，新方法的计算成本要低得多，因为它通过计算向量的时间演化而不是矩阵来获得降密度矩阵，从而使人们能够处理大维系统。作为基准测试，我们考虑了一个量子阻尼谐振子，并表明可以很好地再现精确的结果。除了简化的密度矩阵外，我们的方法还通过引入新的玻色子算子提供了与总波函数的联系。(C) 2019 Elsevier Inc.版权所有。
To investigate a system coupled to a harmonic oscillator bath, we propose a new approach based on a phonon number representation of the bath. Compared to the method of the hierarchical equations of motion, the new approach is computationally much less expensive in a sense that a reduced density matrix is obtained by calculating the time evolution of vectors, instead of matrices, which enables one to deal with large dimensional systems. As a benchmark test, we consider a quantum damped harmonic oscillator, and show that the exact results can be well reproduced. In addition to the reduced density matrix, our approach also provides a link to the total wave function by introducing new boson operators. (C) 2019 Elsevier Inc. All rights reserved.