Phys. Rev. Lett. 111, 073603 (2013)

Nanoscale mechanical resonators have recently reached the quantum regime: laser-induced cooling can prepare such a device in its quantum ground state of just a single phonon. Max Ludwig and Florian Marquardt now demonstrate that arrays of such oscillators could be a convenient solid-state system with which to study phase transitions in complex many-body dynamics.

Ludwig and Marquardt consider a two-dimensional optomechanical lattice driven by a radiation pressure. Photons and phonons are able to move between neighbouring resonators. Their theoretical analysis shows that the collective mechanical motion of this system can change from an incoherent state — when quantum noise prevents the mechanical modes from synchronizing — to an ordered state in which dissipation enables self-induced oscillations to establish themselves. This transition can occur when the optomechanical amplification rate exceeds the intrinsic mechanical damping.

This is not the only way to investigate the dynamics of dissipative systems, but the beauty of the optomechanical approach is that it provides both tunability through optical control and a robust solid-state platform.