Robustifying Twist-and-Turn Entanglement with Interaction-Based Readout

TL;DR

This paper investigates how interaction-based readouts can enhance the robustness of Twist-and-Turn entangled states in atom interferometry against detection noise, outperforming traditional methods like time reversal.

Contribution

It introduces optimized interaction-based readouts for TNT states, demonstrating improved robustness and metrological performance over existing approaches.

Findings

Interaction-based readouts significantly improve noise robustness.

Optimal readout is not necessarily time reversal.

TNT states outperform OAT states in sensitivity.

Abstract

The use of multi-particle entangled states has the potential to drastically increase the sensitivity of atom interferometers and atomic clocks. The Twist-and-Turn (TNT) Hamiltonian can create multi-particle entanglement much more rapidly than ubiquitous one-axis twisting (OAT) Hamiltonian in the same spin system. In this paper, we consider the effects of detection noise - a key limitation in current experiments - on the metrological usefulness of these nonclassical states and also consider a variety of interaction-based readouts to maximize their performance. Interestingly, the optimum interaction-based readout is not the obvious case of perfect time reversal.