Microcavity lasers: Coherent matter and light

V. M. Akulin, Sergey S. Alimpiev, Nikolai V. Karlov +1 more

Desalegn Ayehu, Lmenew Alemu

Deepak Boggavarapu

Thomas H. Doherty, Axel Kuhn, Ezra Kassa

We report the realisation of a high-finesse open-access cavity array, tailored towards the creation of multiple coherent light-matter interfaces within a compact environment. We describe the key technical developments put in place to fabricate such a system, comprising the creation of tapered pyramidal substrates and an in-house laser machining setup. Cavities made from these mirrors are characterised, by laser spectroscopy, to possess similar optical properties to state-of-the-art fibre-tip cavities, but offer a compelling route towards improved performance, even when used to support only a single mode. The implementation of a 2×2 cavity array and the independent frequency tuning between three neighbouring sites are demonstrated.

Caspar Hopfmann, Alexander Carmele, Anna Musiał +5 more

We study experimentally and theoretically a coherently driven strongly coupled quantum dot--microcavity system. Our focus is on physics of the unexplored intermediate excitation regime where the resonant laser field dresses a strongly coupled single exciton-photon (polariton) system resulting in a ladder of laser-dressed Jaynes-Cummings states. In that case, both the coupling of the emitter to the confined light field of the microcavity and to the light field of the external laser are equally important, as proved by observation of injection pulling of the polariton branches by an external laser. This intermediate interaction regime is of particular interest since it connects the purely quantum mechanical Jaynes-Cummings ladder and the semiclassical Autler-Townes ladder. Exploring the driving strength dependence of the mutually coupled system we establish the maximum in the resonance fluorescence signal to be a robust fingerprint of the intermediate regime and observe signatures indicating the laser-dressed Jaynes-Cummings ladder. In order to address the underlying physics we excite the coupled system via the matter component of fermionic nature undergoing saturation---in contrast to commonly used cavity-mediated excitation.

Samuel Serna, Jérèmy Oden, Marc Hanna +6 more