Nanophotonic Interfaces to Control Plasmons and Spins for Quantum Technologies
Research seminar with Laura Kim, Assistant Professor of Materials Science and Engineering, UCLA
ZOOM LINK
Meeting ID: 995 9695 0090
Passcode: 153207
Light-matter interactions mediated by photonic quasiparticles play a crucial role in unlocking phenomena that are not accessible with free-space photons and providing efficient interfaces for quantum systems. In the first part of the presentation, I will present the first experimental demonstration of a mid-infrared light-emitting mechanism originating from an ultrafast coupling of optically excited carriers into hot plasmon excitations in graphene. Such excitations show gate-tunable, non-Planckian emission characteristics due to the atom-level confinement of the electromagnetic states. These findings for plasmon emission in photo-inverted graphene open a new path for the exploration of mid-infrared emission processes, and this mechanism can potentially be exploited for both far-field and near-field applications for strong optical field generation.
In the second part, I will present a resonant metasurface that mediates efficient spin-photon interactions and enables a new type of quantum imaging hardware. This quantum metasurface containing nitrogen-vacancy (NV) spin ensembles coherently encodes information about the local magnetic field on spin-dependent phase and amplitude changes of near-telecom light. The central challenge with NV sensing remains in suboptimal optical readout due to the inefficient spin-photon interface, limiting its achievable sensitivity. In this presentation, I will discuss that nanophotonic strategies provide opportunities to achieve near-unity optical spin readout fidelity for absorption-based readout. This resonant surface is designed to readily couple with external radiation and allow shot-noise-limited sensing with a standard camera, eliminating the need of single-photon detectors. This quantum optical imaging system paves the way for a new type of quantum micro(nano)scopy. The projected performance makes the studied quantum imaging metasurface appealing for the most demanding applications such as imaging through scattering tissues and spatially resolved chemical NMR detection.