论文标题
开放量子系统环境的有效压缩
Efficient Compression Of The Environment Of An Open Quantum System
论文作者
论文摘要
为了模拟开放量子系统，许多方法（例如，动态平均场理论中的基于哈密顿的求解器）的目标是在一组离散的浴室状态下繁殖所需的环境光谱密度，模仿开放系统作为更大的封闭问题。为此目的找到对环境的压缩表示形式的现有策略在数值上是要求的，或者缺乏准确描述系统传播器所需的紧凑性和系统的改进性。我们提出了一种基于响应波函数的Schmidt分解，通过代数结构明确构建浴轨道的方法，有效地和系统地压缩了整个环境的描述。这些由此产生的浴轨道旨在直接重现系统绿色功能而不是杂交系统，从而可以考虑相关的系统能量尺度以最佳模型。这会导致环境的准确有效截断，并在开放量子系统的多种数值模拟中进行了应用。
In order to simulate open quantum systems, many approaches (such as Hamiltonian-based solvers in dynamical mean-field theory) aim for a reproduction of a desired environment spectral density in terms of a discrete set of bath states, mimicking the open system as a larger closed problem. Existing strategies to find a compressed representation of the environment for this purpose can be numerically demanding, or lack the compactness and systematic improvability required for an accurate description of the system propagator. We propose a method in which bath orbitals are constructed explicitly by an algebraic construction based on the Schmidt-decomposition of response wave functions, efficiently and systematically compressing the description of the full environment. These resulting bath orbitals are designed to directly reproduce the system Green's function, not hybridization, which allows for consideration of the relevant system energy scales to optimally model. This results in an accurate and efficient truncation of the environment, with applications in a wide range of numerical simulations of open quantum systems.
