标题： 准粒子能带结构的量子计算与量子选择的组态相互作用 显示英文标题

标题： Quantum computation of a quasiparticle band structure with the quantum-selected configuration interaction

摘要： 准粒子能带结构对于理解强关联电子系统至关重要。尽管在经典计算机上精确求解这些结构具有挑战性，但量子计算提供了一个有前景的替代方案。具体而言，结合变分量子本征值求解器（VQE）的量子子空间展开（QSE）方法提供了一种用于计算准粒子能带结构的量子算法。然而，由于设备噪声、统计噪声以及荒芜高原问题，随着系统规模的增长，优化 VQE 的变分参数变得越来越困难。为了解决这些挑战，我们提出了一种结合 QSE 和量子选择构型相互作用（QSCI）方法的混合方法来计算准粒子能带结构。QSCI 可以利用 VQE 算法作为输入态，但与标准 VQE 不同的是，它不需要完全优化变分参数，这使其更适合于更大的量子系统。基于此方法，我们在 IBM 量子处理器的 16 个量子比特上展示了硅的准粒子能带结构的量子计算。 显示英文摘要

摘要： Quasiparticle band structures are fundamental for understanding strongly correlated electron systems. While solving these structures accurately on classical computers is challenging, quantum computing offers a promising alternative. Specifically, the quantum subspace expansion (QSE) method, combined with the variational quantum eigensolver (VQE), provides a quantum algorithm for calculating quasiparticle band structures. However, optimizing the variational parameters in VQE becomes increasingly difficult as the system size grows, due to device noise, statistical noise, and the barren plateau problem. To address these challenges, we propose a hybrid approach that combines QSE with the quantum-selected configuration interaction (QSCI) method for calculating quasiparticle band structures. QSCI may leverage the VQE ansatz as an input state but, unlike the standard VQE, it does not require full optimization of the variational parameters, making it more scalable for larger quantum systems. Based on this approach, we demonstrate the quantum computation of the quasiparticle band structure of a silicon using 16 qubits on an IBM quantum processor.