Nonreciprocity-enhanced quantum gyroscopes based on surface acoustic waves
Phys. Rev. Applied 25, 034091 – Published 30 March, 2026
DOI: https://doi.org/10.1103/n52d-dr86
Abstract
Surface acoustic waves (SAWs), as elastic waves generated by piezoelectric or piezomagnetic media, have been used in gyroscopes for more than 40 years due to their unique propagation characteristics. However, their working principle, based on Coriolis effects, has become increasingly ineffective for addressing modern sensing challenges in complex scenarios. Fortunately, recent advancements in quantized SAWs offer a promising solution: SAWs operating at extremely low pump powers (approximately at the single-phonon level) can exhibit substantial quantum coherence, enabling investigations into the fundamental limits of SAW gyroscopes as constrained by the Heisenberg uncertainty relation. In particular, when multiple SAWs couple to a common waveguide at distinct locations, the nonlocality arising from the spatial separation among coupling points induces directional coupling between the SAWs. To elucidate this directionality, we propose a quantum gyroscope characterized by multiple-point couplings. Unlike traditional single-point coupling designs, our gyroscope exhibits distinctive time-delayed dynamics that depend on the system’s topologies. Through a comprehensive analysis of all possible topologies, we observe that the directional coupling implies an inherent nonreciprocal transfer. This nonreciprocity confers significant advantages on our gyroscope compared with traditional designs, notably increasing both the signal-to-noise ratio and sensitivity. Specifically, it enables the extraction of output signals that would otherwise be obscured by noise. Consequently, our findings suggest that systems with multiple-point couplings and the associated nonreciprocity can serve as valuable resources for advancing quantum sensing technologies.
