Digital quantum simulation of molecular dynamics and control
Digital quantum simulation of molecular dynamics and control
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DOI：
10.1103/physrevresearch.3.023165
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发表时间：
2021-06-01
影响因子：
4.2
通讯作者：
Sarovar, Mohan
中科院分区：
文献类型：
--
作者：
Magann, Alicia B.;Grace, Matthew D.;Sarovar, Mohan
最佳形状的电磁场具有相干控制量子系统的动力学的能力，从而为控制与化学、生物和材料应用相关的分子转化提供了一种有前途的手段。目前，这一领域的进展受到了量子动力学模拟的高昂成本的阻碍，而量子动力学模拟是探索分子控制的原理和可能性所必需的。然而，新生的量子计算设备的出现表明，量子动力学的有效模拟可能即将出现。在这篇文章中，我们研究了如何利用量子计算机来设计最佳形状的场来控制分子系统。我们介绍了一种混合算法，利用量子计算机在多项式时间内模拟分子系统的场诱导量子动力学，结合经典的优化方法更新字段。描述了与分子控制问题相关的量子比特编码方法，并讨论了量子动力学模拟和获得模拟结果的过程。然后，提出了明确对待范式的振动和旋转控制问题的数值说明，并考虑如何优化形状的字段可以用来阐明在光捕获复合物的能量转移的机制。资源估计，以及硬件噪声的影响和近期硬件实现的前景的数字评估，提供了后一项任务。
Optimally-shaped electromagnetic fields have the capacity to coherently control the dynamics of quantum systems and thus offer a promising means for controlling molecular transformations relevant to chemical, biological, and materials applications. Currently, advances in this area are hindered by the prohibitive cost of the quantum dynamics simulations needed to explore the principles and possibilities of molecular control. However, the emergence of nascent quantum-computing devices suggests that efficient simulations of quantum dynamics may be on the horizon. In this article, we study how quantum computers could be employed to design optimally-shaped fields to control molecular systems. We introduce a hybrid algorithm that utilizes a quantum computer for simulating the field-induced quantum dynamics of a molecular system in polynomial time, in combination with a classical optimization approach for updating the field. Qubit encoding methods relevant for molecular control problems are described, and procedures for simulating the quantum dynamics and obtaining the simulation results are discussed. Numerical illustrations are then presented that explicitly treat paradigmatic vibrational and rotational control problems, and also consider how optimally-shaped fields could be used to elucidate the mechanisms of energy transfer in light-harvesting complexes. Resource estimates, as well as a numerical assessment of the impact of hardware noise and the prospects of near-term hardware implementations, are provided for the latter task.