TY - JOUR T1 - Efficient Product Formulas for Commutators and Applications to Quantum Simulation JF - Physical Review Research Y1 - 2022 A1 - Yu-An Chen A1 - Andrew M. Childs A1 - Mohammad Hafezi A1 - Zhang Jiang A1 - Hwanmun Kim A1 - Yijia Xu AB -

We construct product formulas for exponentials of commutators and explore their applications. First, we directly construct a third-order product formula with six exponentials by solving polynomial equations obtained using the operator differential method. We then derive higher-order product formulas recursively from the third-order formula. We improve over previous recursive constructions, reducing the number of gates required to achieve the same accuracy. In addition, we demonstrate that the constituent linear terms in the commutator can be included at no extra cost. As an application, we show how to use the product formulas in a digital protocol for counterdiabatic driving, which increases the fidelity for quantum state preparation. We also discuss applications to quantum simulation of one-dimensional fermion chains with nearest- and next-nearest-neighbor hopping terms, and two-dimensional fractional quantum Hall phases.

VL - 4 UR - https://arxiv.org/abs/2111.12177 U5 - https://doi.org/10.1103/PhysRevResearch.4.013191 ER -