Heisenberg-limited spin squeezing in coupled spin systems

TL;DR

This paper proposes a universal method to generate Heisenberg-limited spin squeezing in coupled spin systems using collective interactions and continuous driving, enabling high-precision quantum measurements.

Contribution

It introduces a scheme transforming coupled spin interactions into squeezing interactions, achieving extreme squeezing with Heisenberg-limited precision, applicable to many existing systems.

Findings

Achieves Heisenberg-limited measurement scaling as 1/N

Requires only constant, continuous driving fields

Applicable to various physical systems with collective spin interactions

Abstract

Spin squeezing plays a crucial role in quantum metrology and quantum information science. Its generation is the prerequisite for further applications but still faces an enormous challenge since the existing physical systems rarely contain the required squeezing interactions. Here we propose a universal scheme to generate spin squeezing in coupled spin models with collective spin-spin interactions, which commonly exist in various systems. Our scheme can transform the coupled spin interactions into squeezing interactions, and reach the extreme squeezing with Heisenberg-limited measurement precision scaling as $1/N$ for $N$ particles. Only constant and continuous driving fields are required, which is accessible to a series of current realistic experiments. This work greatly enriches the variety of systems that can generate the Heisenberg-limited spin squeezing, with broad applications in quantum precision measurement.