Breakthrough in Phonon Lasers: Groundbreaking Technology for Enhanced Accuracy and Precision

In a major breakthrough, researchers have successfully developed a strategy to achieve multi-color phonon lasers using an active levitated optical mechanical (LOM) system, offering enormous potential for various applications including acoustic imaging, force sensing, and high-precision biomedical sensing.

Phonon lasers, which are mechanical analogues of optical lasers, have shown remarkable characteristics including clear thresholds for transition from thermal to coherent oscillating motion, linewidth narrowing, and squeezing of phonon autocorrelations. Despite these advancements, substantial efforts were needed to overcome the limitations of traditional sound waves, such as random distributions of thermal phonons, and achieve superior coherence.

Researchers at eLight have made a significant milestone by demonstrating a considerable improvement in multiple key features of multi-color phonon lasers through direct application of electronic injection locking into the active LOM system. By controlling the frequency of an alternating current field applied to a microsphere, both the fundamental-mode and higher-order harmonics of the phonon laser can be well locked, leading to giant enhancements of their qualities.

According to the study published in eLight, the brightness of the fundamental-mode phonon laser is enhanced by 3 orders of magnitude compared to previous work, with also 5 orders linewidth narrowing. Additionally, the frequency stability is improved, resulting in a longer trapping lifetime of the micro-object from 1.3 min to over 1.2 hours. Notably, the mechanical quality factor reaches record-highs, at around 6.6 × 106.

The method used by researchers Xiao et al. represents a compelling example for improving the qualities of both fundamental phonon laser mode and its higher-order harmonics. As injection locking is a well-established technique, this breakthrough showcases its vast potential in enhancing the performance of phonon lasers.

This groundbreaking technology drives phonon lasers towards practicality, offering enormous future possibilities in various fields including quantum phononics, multi-frequency mechanical sensors, and high-precision acoustics frequency combs.