Resonant interaction of light with open optical cavities

冯丽丽 FENG Li-li, 阮驰 RUAN Chi, 王允韬 WANG Yun-tao

Rémi Colom, Brian Stout, Nicolas Bonod

Light interaction with optical cavities is of fundamental interest to enhance the light-matter interaction and to shape the spectral features of the electromagnetic fields. Important efforts have been carried out to develop modal theories of open optical cavities relying on an expansion of the fields on the eigen-fields of the cavity. Here, we show how such an expansion predicts the temporal dynamics of optical resonators. We consider a Fabry-Perot cavity to derive the full analytical expressions of the internal and scattered field on the quasi-normal modes basis together with the complex eigen-frequencies. We evince the convergence and accuracy of this expansion before deriving the impulse response function (IRF) of the open cavity. We benefit from this modal expansion and IRF to demonstrate that the eigen-modes of the open cavity impact the signals only during the transient regimes and not in the permanent regime.

C. A. Schrama, Dirk Bouwmeester, Gerard Nienhuis +1 more

G. Keijsers

The ability to control and manipulate light with light is crucial for optical information and communication technology. However, all-optical information processing is hindered by the absence of interactions between photons in linear materials. Nonlinear materials mediate effective photon-photon interactions, but require large light intensity. Optical resonators store and confine light for many optical cycles, which increases the interaction time and reduces the nonlinearity threshold. However, monolithic optical resonators have limited variability of the intra-cavity medium. Instead, a wide variety of materials can be easily integrated in tunable open-access microcavities, making them an ideal platform for exploring novel materials for nonlinear optics. In this thesis, we present experiments using coherently driven tunable open-access microcavities hosting either oil or a perovskite semiconductor. In Chapter 2 we demonstrate steady-state room-temperature superfluidity of photons in an oil-filled cavity, and reveal how the fluid dynamics are influenced by the nonlocality of the effective interactions mediated by the oil. Chapters 3 and 4 describe experiments using a halide perovskite semiconductor in an open-access microcavity in a closed-cycle cryostat. We demonstrate continuous-wave nonlinearity in the halide perovskite material through optical bistability, and reveal signatures of a phase transition in the temperature dependence of the nonlinearity strength. Next we investigate the emergence of irreversibility in the bistable switching of our perovskite cavity. Finally, we present in Chapter 5 experimental observations of fast nonlinearity-enabled oscillations in the light intensity, that occur despite the slowness of thermal nonlinearity of the oil.

Astghik Saharyan, Juan-Rafael Álvarez, Thomas H. Doherty +2 more

We evaluate the exact dipole coupling strength between a single emitter and the radiation field within an optical cavity, taking into account the effects of multilayer dielectric mirrors. Our model allows one to freely vary the resonance frequency of the cavity, the frequency of light or atomic transition addressing it, and the design wavelength of the dielectric mirror. The coupling strength is derived for an open system with unbound frequency modes. For very short cavities, the effective length used to determine their mode volume and the lengths defining their resonances are different, and also found to diverge appreciably from their geometric length, with the radiation field being strongest within the dielectric mirror itself. Only for cavities much longer than their resonant wavelength does the mode volume asymptotically approach that normally assumed from their geometric length.