Achieving Heisenberg Scaling on Measurement of A Three-Qubit System via Quantum Error Correction

TL;DR

This paper demonstrates that periodic quantum error correction enables sustained Heisenberg scaling in measuring a three-qubit system, overcoming decoherence effects in quantum metrology.

Contribution

It introduces two methods showing how quantum error correction can maintain Heisenberg scaling over time in a three-qubit system, with potential generalization to more atoms.

Findings

Heisenberg scaling achieved with error correction

Extended measurement precision over time

Applicable to multi-atom quantum systems

Abstract

In many-body quantum systems, the quantum Fisher information an observer can obtain is susceptible to decoherence. Consequently, quantum enhanced metrology, such as Heisenberg scaling, cannot usually be achieved. We show, via two distinct methods, that by applying periodic quantum error corrections, we can achieve the Heisenberg scaling for an extended period of time on a three-qubit Tavis-Cumming Model, where three two-level atoms interact with a single cavity mode, under certain approximations. The generalization to arbitrary number of atoms case is also discussed.