在时间域内否定和扩展响应函数
Alexander F Kemper1, Chao Yang2, Emanuel Gull3
1Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA.
Physical review letters
|May 3, 2024
概括
对量子系统至关重要的响应函数表现出固有的因果关系. 它们的特性可以减少噪声,并从有限的数据中构建正光谱.
科学领域:
- 量子力学就是量子力学.
- 凝聚物质物理学 凝聚物质物理学
- 量子信息是一种量子信息.
背景情况:
- 响应函数 (例如,电子格林的函数,易感性) 描述了量子系统在外部干扰下的行为.
- 这些函数是量子场理论,量子计算和实验测量中的基本函数.
- 一个关键的属性是它们的内在因果关系,将过去的原因与未来的影响联系起来.
研究的目的:
- 探索响应函数因果关系和光谱属性的含义.
- 展示这些属性如何用于数据分析和理论建模.
- 建立一个框架来构建可靠的实验数据扩展.
主要方法:
- 量子系统中响应函数的理论分析.
- 在平衡/稳定状态下利用因果关系和正光谱函数之间的联系.
- 希尔伯特空间内部积的属性应用于数据处理.
主要成果:
- 在平衡/稳态系统中的响应函数与正光谱函数相对应.
- 响应函数的积极确定的性质允许在测量数据中降低噪声.
- 介绍了一种方法,用于构建有限时间间隔数据的正确确的扩展,以确保正面的光谱.
结论:
- 响应函数的内在因果关系和光谱特性为量子系统分析提供了强大的工具.
- 这些发现有助于提高实验测量和理论预测的准确性.
- 开发的方法确保处理的量子数据的物理有效性 (正光谱).
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