Quantum sensing with a single-qubit pseudo-Hermitian system

Abstract

Quantum sensing exploits fundamental features of quantum system to achieve highly efficient measurement of physical quantities. Here, we propose a strategy to realize a single-qubit pseudo-Hermitian sensor from a dilated two-qubit Hermitian system. The pseudo-Hermitian sensor exhibits divergent susceptibility in dynamical evolution that does not necessarily involve exceptional point. We demonstrate its potential advantages to overcome noises that cannot be averaged out by repetitive measurements. The proposal is feasible with the state-of-art experimental capability in a variety of qubit systems, and represents a step towards the application of non-Hermitian physics in quantum sensing.

6 pages, 3 figure, comments are welcome

References in corpus (7)

• Making Sense of Non-Hermitian Hamiltonians
• The physics of exceptional points
• Ultrasensitive Beam Deflection Measurement via Interferometric Weak Value Amplification
• Observation of parity-time symmetry breaking in a single spin system
• Optimizing the Signal to Noise Ratio of a Beam Deflection Measurement with Interferometric Weak Values
• The Naimark dilated PT-symmetric brachistochrone
• Nano-Scale `Dark State' Optical Potentials for Cold Atoms