论文标题
定期安排的量子模拟
Variationally Scheduled Quantum Simulation
论文作者
论文摘要
本征态制备在量子计算中无处不在,而给定系统中产生最低能量状态的标准方法是采用绝热状态制备(ASP)。在本工作中,我们研究了一种在ASP背景下确定最佳调度程序的变分方法。在没有量子误差校正的情况下,在任何有意义的时间内运行量子设备会导致系统容易受到相关信息丢失的影响。因此,如果要成功生成准确的量子状态,则至关重要的是,找到在退火迭代期间缩短单个运行时间的技术。我们通过研究二维三角晶格上的氢和P4分子以及ISING模型问题来证明我们的变异方法。在这两种情况下,与通过标准ASP可以实现的数量相比,一个迭代产生准确结果所需的时间都会减少几个数量级。结果,通过实现此算法,在量子设备上执行此类计算所需的量子相干时间变得不那么严格。此外,我们发现我们的变异方法表现出针对控制误差的弹性,而控制误差通常在量子计算领域内遇到。
Eigenstate preparation is ubiquitous in quantum computing, and a standard approach for generating the lowest-energy states of a given system is by employing adiabatic state preparation (ASP). In the present work, we investigate a variational method for determining the optimal scheduling procedure within the context of ASP. In the absence of quantum error correction, running a quantum device for any meaningful amount of time causes a system to become susceptible to the loss of relevant information. Therefore, if accurate quantum states are to be successfully generated, it is crucial to find techniques that shorten the time of individual runs during iterations of annealing. We demonstrate our variational method toward this end by investigating the hydrogen and P4 molecules, as well as the Ising model problem on a two-dimensional triangular lattice. In both cases, the time required for one iteration to produce accurate results is reduced by several orders of magnitude in comparison to what is achievable via standard ASP. As a result, the required quantum coherence time to perform such a calculation on a quantum device becomes much less stringent with the implementation of this algorithm. In addition, our variational method is found to exhibit resilience against control errors, which are commonly encountered within the realm of quantum computing.