Birefringent Cavities: Effects and Applications of a New Paradigm in CQED

The enhanced interaction of quantum states of light and matter within an optical resonator is a powerful tool for both addressing fundamental questions of nature and pursuing quantum technologies. Here, we discuss the impact of cavity birefringence - a lifting of the degeneracy of polarisation modes within the resonator - on both of these challenges. A novel model for such systems is experimentally verified by the cavity emission of single photons with time-dependent polarisation states that evolve along their wavepacket [1]. This model is then used to demonstrate how a tailored birefringence allows for enhanced photon emission beyond previous limitations [2].