Teplukhin Alexander, Kendrick Brian K, Tretiak Sergei, Dub Pavel A
Theoretical Division (T-1, MS B221), Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.
Chemistry Division (C-IIAC, MS K558), Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.
Sci Rep. 2020 Nov 27;10(1):20753. doi: 10.1038/s41598-020-77315-4.
Quantum chemistry is regarded to be one of the first disciplines that will be revolutionized by quantum computing. Although universal quantum computers of practical scale may be years away, various approaches are currently being pursued to solve quantum chemistry problems on near-term gate-based quantum computers and quantum annealers by developing the appropriate algorithm and software base. This work implements the general Quantum Annealer Eigensolver (QAE) algorithm to solve the molecular electronic Hamiltonian eigenvalue-eigenvector problem on a D-Wave 2000Q quantum annealer. The approach is based on the matrix formulation, efficiently uses qubit resources based on a power-of-two encoding scheme and is hardware-dominant relying on only one classically optimized parameter. We demonstrate the use of D-Wave hardware for obtaining ground and excited electronic states across a variety of small molecular systems. The approach can be adapted for use by a vast majority of electronic structure methods currently implemented in conventional quantum-chemical packages. The results of this work will encourage further development of software such as qbsolv which has promising applications in emerging quantum information processing hardware and has expectation to address large and complex optimization problems intractable for classical computers.
量子化学被认为是最早将被量子计算彻底改变的学科之一。尽管实用规模的通用量子计算机可能还需要数年时间才能实现，但目前正在探索各种方法，通过开发合适的算法和软件基础，在近期基于门的量子计算机和量子退火器上解决量子化学问题。这项工作实现了通用量子退火器本征解算器（QAE）算法，以在D-Wave 2000Q量子退火器上解决分子电子哈密顿量本征值-本征向量问题。该方法基于矩阵公式，基于二进制编码方案有效地利用量子比特资源，并且仅依赖一个经典优化参数，以硬件为主导。我们展示了使用D-Wave硬件来获取各种小分子系统的基态和激发态电子态。该方法可适用于目前在传统量子化学软件包中实现的绝大多数电子结构方法。这项工作的结果将鼓励进一步开发诸如qbsolv之类的软件，该软件在新兴的量子信息处理硬件中有很有前景的应用，并有望解决经典计算机难以处理的大型复杂优化问题。
