UNconventional Integrated quantum nanophotonic sources From spontaneous sYmmetry breaking

ended

The integration of reliable quantum sources on a photonic microchip is at heart of intense research in today quantum photonics. Our project is devoted to the realization of quantum correlations such as photon entanglement based on nonlinear interactions in semiconductor coupled nanocavities, ultimately with few photons. Unlike conventional semiconductor quantum sources that require deterministic coupling of emitters into small cavities and/or operation at ultralow temperatures, UNIFY will achieve unconventional sources with quantum correlations using Indium Phosphide-based bulk or quantum well photonic crystal cavities on Silicon, on-chip integrable and operating at room temperature in the telecommunication band. UNIFY relies on a recent theoretical prediction: photon entanglement from nonlinear optical transitions –i.e. bifurcations– in coupled cavity systems, such as spontaneous symmetry breaking (SSB). SSB-induced quantum correlations will be sought with either weak nonlinearities per photon and strong fields (continuous variable), or relatively large nonlinearities per photon in a few photon regime. UNIFY proposes to tackle them using a twofold strategy: passive (coherent excitation), and active (nanolaser) experimental configurations. For the latter, cavities with large spontaneous emission factor (β) will be realized to decrease the saturation photon number. The combination of nanocavities with tunable inter-cavity evanescent coupling, high-quality factors, ultra-small mode volumes, efficient input/output light coupling and high β-factors will ultimately lower the intracavity photon number below ~10. Such a platform is compatible with device integration on a photonic microchip, small footprint and scalability. We thus propose to unify an outstanding early career researcher with experience on coherent excitation SSB and world leaders in nanophotonics and quantum optics in order to enable a new generation of unconventional quantum photonic nanosources.