Precision measurement serves as a cornerstone for exploring the laws of nature and driving technological transformation, with quantum precision measurement offering a revolutionary pathway to surmount classical physical limits. Phonon lasers, as the acoustic analog of optical lasers, generate highly coherent mechanical oscillations through stimulated gain processes, emerging as a crucial research frontier in quantum sensors. This comprehensive review systematically outlines the fundamental principles, diverse physical implementation platforms, and state-of-the-art applications of phonon lasers in quantum precision measurement, aiming to provide a vital reference for interdisciplinary research in micro-nano optomechanics and quantum information.
Methodologically, this review constructs a unified theoretical framework to describe the dynamics of phonon lasers across different scales. From a classical perspective, the generation of phonon lasers is explained via a dynamic ”negative damping” mechanism that drives the mechanical mode across a Hopf bifurcation threshold into a stable limit-cycle oscillation. In the quantum regime, we utilize the Lindblad master equation to elucidate the transition of phonon states from thermal fluctuations to coherent radiation via controlled stimulated energy exchange. With this framework established, we comparatively analyze three mainstream physical platforms: trapped-ion systems that leverage internal electronic state transitions for ultra-high coherence, cavity optomechanical systems driven by radiation pressure for macroscopic chip-scale integration, and optically levitated nanospheres that utilize active non-linear electro-optic feedback for long-term stable sensing.
The core results of this review highlight the exceptional nonlinear amplification capabilities of phonon lasers across multiple sensing paradigms. In electric field and weak force detection, injection-locking mechanisms enable the mapping of ultra-weak oscillatory drives into macroscopic coherent phase responses, achieving yoctonewton-level (yN) to zeptonewton-level (zN) force sensitivities. For mass sensing, the active gain compensation of phonon lasers substantially compresses the mechanical linewidth from the MHz to the kHz regime, overcoming fluidic dissipation to achieve zeptogram-level (zg) mass resolution under ambient conditions. Furthermore, non-reciprocal phonon lasers leveraging the Sagnac effect in rotating microcavities, alongside on-chip Brillouin acoustic gyroscopes, demonstrate profound potential for sub-shot-noise angular momentum sensing. Notably, the recent integration of Floquet engineering has facilitated the generation of fully coherent phonon laser frequency combs comprising thousands of phaselocked teeth, bridging a critical gap for broad-bandwidth underwater and biomedical acoustic sensing.
In conclusion, while phonon lasers present transformative advantages for quantum sensing, their practical deployment faces challenges such as long-term phase diffusion and cross-platform integration bottlenecks, including anomalous heating in surface-electrode ion traps and thermal dissipation in nanomechanical cavities. Future trajectories must focus on developing large-scale phonon laser arrays, achieving robust room-temperature operation, and exploiting non-classical squeezed or entangled phonon states to ultimately push measurement sensitivities toward the Heisenberg limit.