标题： 算子投影变分量子虚时间演化 显示英文标题

标题： Operator-Projected Variational Quantum Imaginary Time Evolution

摘要： 变分量子虚时演化（VQITE）是量子计算机上制备基态的领先技术。 VQITE的一个显著计算挑战是确定量子几何张量。 我们表明，只要虚时演化在投影到选定的一组算符上时是正确的，就可以通过绕过保真度估计来实现电路深度的两倍减少，并将测量复杂度从参数数量的二次方降低到线性。 我们通过横向场伊辛模型的模拟证明，我们的算法在相同精度下所需的测量次数有数个数量级的改进。 显示英文摘要

摘要： Variational Quantum Imaginary Time Evolution (VQITE) is a leading technique for ground state preparation on quantum computers. A significant computational challenge of VQITE is the determination of the quantum geometric tensor. We show that requiring the imaginary-time evolution to be correct only when projected onto a chosen set of operators allows to achieve a twofold reduction in circuit depth by bypassing fidelity estimations, and reduces measurement complexity from quadratic to linear in the number of parameters. We demonstrate by a simulation of the transverse-field Ising model that our algorithm achieves a several orders of magnitude improvement in the number of measurements required for the same accuracy.