Circuit-Efficient Qubit-Excitation-based Variational Quantum Eigensolver

Zhijie Sun; Jie Liu; Zhenyu Li; Jinlong Yang

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arXiv · 2406.11699

Circuit-Efficient Qubit-Excitation-based Variational Quantum Eigensolver

Zhijie Sun·Jie Liu·Zhenyu Li·Jinlong Yang

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Abstract

The wave function Ansatze are crucial in the context of the Variational Quantum Eigensolver (VQE). In the Noisy Intermediate-Scale Quantum era, the design of low-depth wave function Ansatze is of great importance for executing quantum simulations of electronic structure on noisy quantum devices. In this work, we present a circuit-efficient implementation of two-body Qubit-Excitation-Based (QEB) operator for building shallow-circuit wave function Ansatze within the framework of Adaptive Derivative-Assembled Pseudo-Trotter (ADAPT) VQE. This new algorithm is applied to study ground- and excited-sate problems for small molecules, demonstrating significant reduction of circuit depths compared to fermionic excitation-based and QEB ADAPT-VQE algorithms. This circuit-efficient algorithm shows great promise for quantum simulations of electronic structures, leading to improved performance on current quantum hardware.

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Zhijie Sun, Jie Liu, Zhenyu Li, Jinlong Yang. 2024-06-17. Circuit-Efficient Qubit-Excitation-based Variational Quantum Eigensolver. https://arxiv.org/abs/2406.11699

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