Advantage of Warm Starts for Electron-Phonon Systems on Quantum Computers

TL;DR

This paper demonstrates that using physically informed initial states significantly improves the efficiency of quantum simulations of electron-phonon systems, reducing circuit costs and iteration counts.

Contribution

It introduces an initial-state ansatz for the Holstein model that enhances ground state overlap and reduces quantum resource requirements.

Findings

Exponential reduction in circuit costs with the new ansatz

Enhanced ground state overlap in strong coupling regimes

Efficient implementation of the initial-state ansatz

Abstract

Simulating electron-phonon interactions on quantum computers remains challenging, with most algorithmic effort focused on Hamiltonian simulation and circuit optimization. In this work, we study the single-electron Holstein model and propose an initial-state ansatz that substantially enhances ground state overlap in the strong coupling regime, thereby reducing the number of iterations required in standard quantum phase estimation. We further show that this ansatz can be implemented efficiently and yields an exponential reduction in overall circuit costs relative to conventional initial guesses. Our results highlight the practical value of incorporating physical intuition into initial state preparation for electron-phonon coupled systems.