Towards on-chip generation, routing and detection of non-classical light

We fabricate an integrated photonic circuit with emitter, waveguide and detector on one chip, based on a hybrid superconductor-semiconductor system. We detect photoluminescence from self-assembled InGaAs quantum dots on-chip using NbN superconducting nanowire single photon detectors. Using the fast temporal response of these detectors we perform time-resolved studies of non-resonantly excited quantum dots. By introducing a temporal filtering to the signal, we are able to resonantly excite the quantum dot and detect its resonance uorescence on-chip with the integrated superconducting single photon detector.Comment: 9 pages, 5 figure

Dynamic acousto-mechanical control of a strongly coupled photonic molecule

Two-dimensional photonic crystal membranes provide a versatile planar architecture for integrated photonics to control the propagation of light on a chip employing high quality optical cavities, waveguides, beamsplitters or dispersive elements. When combined with highly non-linear quantum emitters, quantum photonic networks operating at the single photon level come within reach. Towards large-scale quantum photonic networks, selective dynamic control of individual components and deterministic interactions between different constituents are of paramount importance. This indeed calls for switching speeds ultimately on the system's native timescales. For example, manipulation via electric fields or all-optical means have been employed for switching in nanophotonic circuits and cavity quantum electrodynamics studies. Here, we demonstrate dynamic control of the coherent interaction between two coupled photonic crystal nanocavities forming a photonic molecule. By using an electrically generated radio frequency surface acoustic wave we achieve optomechanical tuning, demonstrate operating speeds more than three orders of magnitude faster than resonant mechanical approaches. Moreover, the tuning range is large enough to compensate for the inherent fabrication-related cavity mode detuning. Our findings open a route towards nanomechanically gated protocols, which hitherto have inhibited the realization in all-optical schemes.Comment: submitted manuscrip

Phonon-assisted transitions from quantum dot excitons to cavity photons

For a single semiconductor quantum dot embedded in a microcavity, we theoretically and experimentally investigate phonon-assisted transitions between excitons and the cavity mode. Within the framework of the independent boson model we find that such transitions can be very efficient, even for relatively large exciton-cavity detunings of several millielectron volts. Furthermore, we predict a strong detuning asymmetry for the exciton lifetime that vanishes for elevated lattice temperature. Our findings are corroborated by experiment, which turns out to be in good quantitative and qualitative agreement with theory