Operator-projected variational quantum imaginary time evolution
Abstract
Abstract 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.
Fields of Study & Subjects
Advanced Thermodynamics and Statistical Mechanics
Opinion Dynamics and Social Influence
Publication details
- Journal / source
- Journal of Physics A Mathematical and Theoretical
- Publisher
- IOP Publishing
- Volume
- 59
- Issue
- 24
- Pages
- 245301–245301
- Publication date
- 2 June 2026
- Language
- EN