Model-Independent Error Mitigation in Parametric Quantum Circuits and Depolarizing Projection of Quantum Noise

TL;DR

This paper introduces a noise error mitigation technique for parametric quantum circuits that projects general noise onto depolarization errors, improving the accuracy of quantum computations on NISQ devices.

Contribution

It presents a novel, efficient error mitigation scheme based on depolarizing projection, applicable to variational quantum algorithms on noisy quantum hardware.

Findings

The method effectively reduces errors in quantum simulations.

Successful demonstration on classical and IBM quantum devices.

Accurate computation of the transverse-field Ising model's mass gap.

Abstract

Finding ground states and low-lying excitations of a given Hamiltonian is one of the most important problems in many fields of physics. As a novel approach, quantum computing on Noisy Intermediate-Scale Quantum (NISQ) devices offers the prospect to efficiently perform such computations and may eventually outperform classical computers. However, current quantum devices still suffer from inherent quantum noise. In this work, we propose an error mitigation scheme suitable for parametric quantum circuits. This scheme is based on projecting a general quantum noise channel onto depolarization errors. Our method can efficiently reduce errors in quantum computations, which we demonstrate by carrying out simulations both on classical and IBM's quantum devices. In particular, we test the performance of the method by computing the mass gap of the transverse-field Ising model using the variational quantum eigensolver algorithm.