Quantum-enhanced sensing of spin-orbit coupling without fine tuning

TL;DR

This paper demonstrates a quantum sensing method using a 1D quantum wire to estimate spin-orbit coupling with enhanced precision that surpasses classical limits, without the need for fine tuning, applicable to both single particles and many-body systems.

Contribution

It introduces a quantum sensing approach leveraging gap-closing properties for robust, high-precision estimation of spin-orbit coupling without fine tuning, applicable to various quantum states.

Findings

Achieved Heisenberg-limited sensitivity across a wide parameter range.

Demonstrated quantum enhancement for both single particle and many-body probes.

Extended results to thermal states and multi-parameter estimation scenarios.

Abstract

Spin-orbit coupling plays an important role in both fundamental physics and technological applications. Precise estimation of the spin-orbit coupling is necessary for accurate designing across various physical setups such as solid state devices and quantum hardware. Here, we exploit quantum features in a 1D quantum wire for estimating the Rashba spin-orbit coupling with enhanced sensitivity beyond the capability of classical probes. The Heisenberg limited enhanced precision is achieved across a wide range of parameters and does not require fine tuning. Such advantage is directly related to the gap-closing nature of the probe across the entire relevant range of parameters. This provides clear advantage over conventional criticality-based quantum sensors in which quantum enhanced sensitivity can only be achieved through fine-tuning around the phase transition point. We have demonstrated quantum enhanced sensitivity for both single particle and interacting many-body probes. In addition to extending our results to thermal states and the multi-parameter scenario, we have provided an measurement basis to perform close to the ultimate precision.