Manipulating the mid-infrared quantum field statistics with molecular polaritons in the strong and ultrastrong coupling regime*

Controlling the quantum statistics of the electromagnetic field is one of the biggest challenges in quantum optics and nanophotonics in the mid-infrared regime. In this work, we propose that by coupling molecular vibrations with the vacuum in a Fabry-Perot cavity, the photon number and quadratures of the intracavity electromagnetic field can be modified by pumping one cavity mirror with ultrafast UV pulses. We show that modulating the cavity frequency by ~15% leads to strong variations of the Mandel Q-factor and squeezing of order ~1 dB of the intracavity field, for a system initially prepared in the experimentally relevant ground or lower polariton state. The adiabatic modulation of the cavity frequency produces sub-Poissonian infrared light when the system is initialized in a super-Poissonian ground polariton state. We also describe the dependence of the cavity field statistics with the electric dipole behavior and the spectral anharmonicity of molecular vibrations. This proposal opens new routes in the development of mid-infrared quantum optical devices at room temperature using molecular vibrations in confined electromagnetic fields.