相关实验视频
Updated: Feb 6, 2026

06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
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减少密度矩阵和量子线性响应的累积近似值
Theo Juncker von Buchwald1, Erik Rosendahl Kjellgren2, Jacob Kongsted2
1Department of Chemistry, Technical University of Denmark, Kemitorvet Building 207, Kongens Lyngby DK-2800, Denmark.
Journal of chemical theory and computation
|February 5, 2026
概括
通过单元和双元 (qLRSD) 进行近似量子线性响应 (qLR) 显示了减少量子工作负载的前景. 然而,对3体减少密度矩阵 (RDMs) 的近似失败,而4体近似则难以获得强烈的相关性.
科学领域:
- 量子计算是一种量子计算.
- 计算化学是一种计算化学.
- 理论化学是一种理论化学.
背景情况:
- 线性响应 (LR) 是一个重要的计算化学工具.
- 量子计算提供了一个量子对应物,量子LR (qLR).
- 短期中等尺度量子 (NISQ) 设备面临着噪声和脱凝的挑战.
研究的目的:
- 开发qLR的近似来降低量子计算成本.
- 研究近似减少密度矩阵 (RDM) 和减少密度累积物 (RDC) 对qLR精度的影响.
- 分析与qLR相关的测量成本.
主要方法:
- 简单的qLR与单打和双打的qLR的近似值 (qLRSD).
- 直接接近RDMs或通过RDCs间接接近.
- 使用RDMs对qLR的测量成本的分析.
- qLRSD应用于各种化学系统,包括梯,OCS,SeH2,H2S,H2O和BeH2.
主要成果:
- 对四体RDM和RDC的近似计算为平衡几何和一些核心激发提供了良好的结果.
- 对于具有强相关性的系统,四体近似失败.
- 所有涉及三体RDM和/或RDC的近似方法都会显著降低结果,并且是不可行的.
结论:
- qLRSD近似显示了减少量子工作负载的潜力,但需要仔细考虑相关性效应.
- 对三体RDM/RDC的近似方法不适合qLR.
- 需要进一步的研究,以开发强烈相关的系统的强大的qLR近似.
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