Heisenberg-limited Sagnac interferometer with multiparticle states

Abstract

The Sagnac interferometry has been widely used to measure rotation frequency. Beyond the conventional single-particle Sagnac interferometry, we propose an atomic Sagnac interferometry via multi-particle entangled states. In our scheme, an ensemble of entangled two-state Bose atoms are moved in a ring by a state-dependent rotating potential and then are recombined for interference via Ramsey pulses after a specific time determined by the state-dependent rotating potential. The ultimate rotation sensitivity can be improved to the Heisenberg limit if the initial internal degrees of freedom are entangled. By implementing parity measurement, the ultimate measurement precision can be saturated and the achieved measurement precisions approach to the Heisenberg limit. Our results provide a promising way to exploit many-body quantum entanglement in precision metrology of rotation sensing.

Multiqubit matter-wave interferometry under decoherence and the Heisenberg scaling recovery

“…[12], and was later generalized to the one with multiparticle Greenberger-Horne-Zeilinger (GHZ) state to beat the standard quantum limit (SQL) in Ref. [13]. So far, these proposed schemes were considered in ideal situations where the sensing protocols consisted of perfect unitary quantum channels.…”

Quantum-Enhanced Fiber-Optic Gyroscopes Using Quadrature Squeezing and Continuous Variable Entanglement

“…Recent developments include hollow core fiber coils [31], integrated optical sources and homodyne detectors, and laser-driven FOGs that bypass the conventional requirement for temporally incoherent sources [32,33]. In addition, quantum-enhancement has recently been considered to boost rotation sensitivity [34][35][36][37][38][39][40][41], and preliminary experimental works on quantum-enhanced FOGs have demonstrated improvements via injection of squeezed vacuum [35] and entangled NOON states [39].…”

Noisy quantum gyroscope

“…It was found that the entanglement in N00N states [29,30], continuous-variable squeezing [31][32][33], and optical nonlinearity [34] can enhance the sensitivity of optical gyroscopes beyond the SNL. A quantumenhanced sensitivity can also be achieved in matter-wave gyroscopes [35][36][37][38] by using spin squeezing [39][40][41] or entanglement. However, quantum gyroscopes are still at the stage proof-of-principle study and their superiority over the conventional ones in the absolute value of sensitivity still has not been exhibited [22,37].…”