论文标题
规范上一致的量子主方程
Canonically consistent quantum master equation
论文作者
论文摘要
我们提出了一类新的量子主方程,该方程正确地重现了无限弱的系统浴耦合极限以外的开放量子系统的渐近状态。我们的方法基于将降低稳态的知识纳入其动力学中。校正不仅将减少的系统转向正确的稳态,还提高了动力学的准确性,从而完善了原型Born-Markov弱耦合二阶主方程。在平衡的情况下,由于存在平均力吉布斯状态的稳态封闭形式,因此我们利用此形式纠正Redfield量子主方程。使用确切的可解决的谐波振荡器系统,我们用确切的解决方案对我们的方法进行基准测试,表明我们的方法还有助于纠正长期存在的违规阳性问题,尽管没有完全阳性。我们的规范上一致的量子主方程的方法在开放量子系统的理论中打开了一个新的视角,从而使密度降低的密度矩阵准确地超出了常用的红菲尔德和lindblad方程,同时保留了相同的概念和数值复杂性。
We put forth a new class of quantum master equations that correctly reproduce the asymptotic state of an open quantum system beyond the infinitesimally weak system-bath coupling limit. Our method is based on incorporating the knowledge of the reduced steady state into its dynamics. The correction not only steers the reduced system towards a correct steady state but also improves the accuracy of the dynamics, thereby refining the archetypal Born-Markov weak-coupling second-order master equations. In case of equilibrium, since a closed form for the steady state exists in terms of a mean force Gibbs state, we utilize this form to correct the Redfield quantum master equation. Using an exactly solvable harmonic oscillator system we benchmark our approach with the exact solution showing that our method also helps correcting the long-standing issue of positivity violation, albeit without complete positivity. Our method of a canonically consistent quantum master equation, opens a new perspective in the theory of open quantum systems leading to a reduced density matrix accurate beyond the commonly used Redfield and Lindblad equations, while retaining the same conceptual and numerical complexity.