Optimizing stochastic trajectories in exact quantum-jump approaches of interacting systems
Optimizing stochastic trajectories in exact quantum-jump approaches of interacting systems
复制标题
优化交互系统精确量子跳跃方法中的随机轨迹
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
D. Lacroix
中科院分区：
文献类型：
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作者：
D. Lacroix
量子跳跃的方法，其中对状态矢量遵循随机薛定谔方程（SSE），以处理两个相互作用系统的精确量子动力学，被描述。在这项工作中，这种随机薛定谔方程的非唯一性进行了研究，提出策略，以优化随机路径，减少统计波动。在所提出的方法中，称为“自适应噪声方法”，获得一个特定的SSE，其中噪声明确地依赖于初始状态和相互作用哈密顿量的属性。它还表明，这种方法可以进一步改进，通过引入平均场动力学。不同的优化程序的情况下，相互作用的自旋定量说明。一个显着减少的统计波动。因此，与没有优化的SSE相比，需要更少数量的轨迹来准确地再现精确的动力学。
The quantum-jump approach, where pairs of state vectors follow the stochastic Schroedinger equation (SSE) in order to treat the exact quantum dynamics of two interacting systems, is described. In this work the nonuniqueness of such stochastic Schroedinger equations is investigated to propose strategies to optimize the stochastic paths and reduce statistical fluctuations. In the proposed method, called the ``adaptative noise method,' a specific SSE is obtained for which the noise depends explicitly on both the initial state and on the properties of the interaction Hamiltonian. It is also shown that this method can be further improved by introduction of a mean-field dynamics. The different optimization procedures are illustrated quantitatively in the case of interacting spins. A significant reduction of the statistical fluctuations is obtained. Consequently a much smaller number of trajectories is needed to accurately reproduce the exact dynamics as compared to the SSE without optimization.