Calculation of Gibbs partition function with imaginary time evolution on near-term quantum computers
Abstract
The Gibbs partition function is an important quantity in describing statistical properties of a system in thermodynamic equilibrium. There are several proposals to calculate the partition functions on near-team quantum computers. However, the existing schemes require many copies of the Gibbs states to perform an extrapolation for the calculation of the partition function, and these could be costly performed on the near-term quantum computers. Here, we propose an efficient scheme to calculate the Gibbs function with the imaginary time evolution. To calculate the Gibbs function of qubits, only qubits are required in our scheme. After preparing Gibbs states with different temperatures by using the imaginary time evolution, we measure the overlap between them on a quantum circuit, and this allows us to calculate the Gibbs partition function.
Cite
@article{arxiv.2109.14880,
title = {Calculation of Gibbs partition function with imaginary time evolution on near-term quantum computers},
author = {Keisuke Matsumoto and Yuta Shingu and Suguru Endo and Shiro Kawabata and Shohei Watabe and Tetsuro Nikuni and Hideaki Hakoshima and Yuichiro Matsuzaki},
journal= {arXiv preprint arXiv:2109.14880},
year = {2022}
}