Phonon lasing creation and transfer in an optically levitated nanopartical system

Phonon lasers are extensively researched as mechanical counterparts to optical lasers for various applications. An optical tweezer phonon laser was developed, but it only affected one degree of movement. To address this, we introduced a multimode levitated nanoparticle to transfer coherence between different oscillation directions. Coupling was achieved by rotating the asymmetric optical potential via trap laser polarization rotation. The change in power spectral density showed the feature of lasing transfer before and after coupling, and the mean phonon number of the system was saturated. Coherence was confirmed by measuring second-order auto-correlation function of the oscillation modes. Coupled laser systems have potential in precision measurement and quantum information processing.