Bose-Hubbard model with a single qubit

TL;DR

This paper demonstrates the use of a single-qubit parametrized quantum circuit as an Ansatz for calculating the ground state energy of the 1D Bose-Hubbard model, comparing it to neural network methods and implementing on IBM hardware.

Contribution

It introduces a novel single-qubit quantum Ansatz for the Bose-Hubbard model and compares its performance to neural network approaches and classical computations.

Findings

Single-qubit Ansatz achieves comparable accuracy to neural network methods.

Quantum hardware implementation validates practical feasibility.

Potential for scalable quantum simulation of many-body systems.

Abstract

The use of a single-qubit parametrized circuit as an Ansatz for the variational wave function in the calculation of the ground state energy of a quantum many-body system is demonstrated using the one-dimensional Bose-Hubbard model. Comparison is made to calculations where a classic neural network is used to generate the variational wave function. Computations carried out on IBM Quantum hardware are also presented.