Petr Zapletal

Research

I am generally interested in studying many body physics using quantum optical systems.

In particular, I am focused on the field of optomechanics describing the interaction between light and mechanical oscillators due to radiation pressure of photons deflecting off the oscillators. Optomechanical experiments have shown cooling of a nano-mechanical mode into the vibrational ground state and measurement of mechanical motion with a record precision to name but a few achievements. This progress in optomechanical control allows to probe quantum physics on mesoscale. Coupling of several mechanical and optical modes in optomechanical arrays opened a possibility to study many body physics. In such a setting, synthetic gauge fields for photons and phonons can be implemented to mimic effects of magnetic and electric fields. Together with reservoir engineering, synthetic magnetic fields led to nonreciprocal transport of photons and phonons. I have recently investigated backaction of particles’ movement on dynamical gauge fields, which undergo their own dynamics. In this dynamical situation, which naturally arises in optomechanics, synthetic electric field for photons can be generated and affect light propagation. We have demonstrated that nonlinear dynamics of gauge fields can result in unidirectional light transport even in one-dimensional arrays where no magnetic field is present.

In the future, I plan to investigate other nonlinear phenomena in optomechanical arrays. For example synchronization, which describes tendency of self-oscillators to match their phases and frequencies either within themselves or to an external drive. Novel quantum signatures of synchronization have been recently investigated in optomechanics and other platforms. Another possible direction is topological phases for sound and light. Due to recent progress in reservoir engineering, optomechanical arrays provide natural setting for studying interplay between topology and dissipation described by non-hermitian Hamiltonians.