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Updated: May 14, 2025

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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
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阶段空间测量,不连贯性和古典性
Dorje C Brody1,2, Eva-Maria Graefe3, Rishindra Melanathuru3
1University of Surrey, School of Mathematics and Physics, Guildford GU2 7XH, United Kingdom.
Physical review letters
|April 11, 2025
概括
环境监测导致量子系统失去量子性质,这一过程称为脱凝. 这项研究模拟了相空间测量的脱凝,显示它导致位置和动量的对角化.
科学领域:
- 量子物理学的量子物理学
- 量子信息理论就是量子信息理论.
- 环境不连贯性 环境不连贯性
背景情况:
- 经典行为源于量子系统与其环境的相互作用.
- 环境监测通过减轻密度矩阵的离对角元素导致脱凝.
- 不连贯性通常是使用由位置运算符驱动的林布拉德方程来建模的.
研究的目的:
- 为了解决由同时监测位置和动量 (相位空间测量) 引起的不连贯性.
- 为了克服由于海森堡不确定性原理,对于相空间点没有可观测的标准量子的挑战.
- 模拟相位空间监测,使用基于连贯状态的积极操作员值的指标.
主要方法:
- 使用一个连贯的基于国家的积极运营商估值指标 (POVM).
- 建模环境监测位置和动量.
- 在相空间中分析密度矩阵的含义.
主要成果:
- 阶段空间中的非连贯性导致在位置和动量表示中密度矩阵的对角化.
- 这个过程在数学上与林布拉德方程有关.
- 在这个模型中,位置和动量作为独立的林德布拉德运算符.
结论:
- 环境相位空间监测诱导脱凝,导致古典行为.
- 开发的POVM方法为理解相位空间中的非连贯性提供了一个框架.
- 这项工作扩大了对不连贯性的理解,超出了单一可观测的监测范围.
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