论文标题
工程为在近期设备上实施的跨量子算法的成本函数
Engineering the Cost Function of a Variational Quantum Algorithm for Implementation on Near-Term Devices
论文作者
论文摘要
变分杂种量子古典算法是近期量子计算机最有前途的工作负载，而无需校正。这些变异算法的目的是通过改变量子电路中的某些参数，将量子系统引导到最小化成本函数的目标状态。本文提出了一种新的工程成本功能的方法，以提高当今小型量子系统上某些类别算法的性能。我们将这种方法应用于生成横向场模型的热场双状态的变分算法，在研究凝结物质系统中的相变时，它们在研究时很重要。我们讨论了各种成本功能的好处和缺点，应用我们的新工程方法，并表明它在整个温度范围内产生了良好的一致性。
Variational hybrid quantum-classical algorithms are some of the most promising workloads for near-term quantum computers without error correction. The aim of these variational algorithms is to guide the quantum system to a target state that minimizes a cost function, by varying certain parameters in a quantum circuit. This paper proposes a new approach for engineering cost functions to improve the performance of a certain class of these variational algorithms on today's small qubit systems. We apply this approach to a variational algorithm that generates thermofield double states of the transverse field Ising model, which are relevant when studying phase transitions in condensed matter systems. We discuss the benefits and drawbacks of various cost functions, apply our new engineering approach, and show that it yields good agreement across the full temperature range.
