Towards Coherent Light-Matter Interaction in the Solid State at Room Temperature

Coherent interaction between light and a material system is a major prerequisite for a quantum network, as it enables quantum information transfer between photons, serving as flying qubits (the links of the network) and localized electrons, serving as anchored qubits (the nodes of the network). Such a network can be a scalable platform for quantum information processing, provided its building blocks are based on scalable technologies such as solid-state nano photonic devices. Operation at non-cryogenic temperatures is another beneficial requirement, as it considerably reduces overhead due to cooling systems. Optical photons already preserve coherence at elevated temperatures. So do some electron or nuclear spin systems in non-magnetic solid materials, such as point defects in diamond. The challenge is then the creation of a coherent link between them at elevated temperatures. In this talk I’ll discuss the quantum-optical memory, a basic light-matter interface, as an instructive example. I’ll review the current state of the art, and present two possible pathways towards coherent light-matter interaction in the solid state at room temperature.