Static Quantum Errors and Purification

TL;DR

This paper introduces a purification protocol to suppress static errors in quantum state preparation and measurement, demonstrating effectiveness with few qubits and realistic scenarios, using current quantum technology.

Contribution

The work presents a novel purification protocol for static errors in quantum SPAM, applicable to noisy resources and verified through practical scenarios.

Findings

Effective error suppression with few qubits up to 10^{-3} error rate

Protocol feasible with current quantum technologies

Demonstrated in realistic quantum system scenarios

Abstract

State preparation that initializes quantum systems in a fiducial state and measurements to read outcomes after the evolution of quantum states, both essential elements in quantum information processing in general, may contain noise from which errors, in particular, referred to as static errors, may appear even with noise-free evolution. In this work, we consider noisy resources such as faulty manufacturing and improper maintenance of systems by which static errors in state preparation and measurement are inevitable. We show how to suppress static errors and purify noiseless SPAM by repeatedly applying noisy resources. We present the purification protocol for noisy initialization and noisy measurements and verify that a few qubits are immediately cost-effective to suppress error rates up to $10^{-3}$. We also demonstrate the purification protocol in a realistic scenario. The results are readily feasible with current quantum technologies.