Quantum Coherence in Nano-and Micro-Photonics

Abstract

The principle of complementarity refers to the ability of quantum entities to behave as particles or waves under different experimental conditions. I discuss a recently proposed device enabling the ultrafast all optical control of the wave‐particle duality of light. It is constituted by a three‐level quantum emitter strongly coupled to a microcavity and can be realized by exploiting a great variety of systems ranging from atomic physics and semiconductor quantum dots to intersubband polaritons and Cooper pair boxes. Control pulses with specific arrival times, performing which‐path and quantum‐eraser operations, are able to destroy and recover interference almost instantaneously. I will also discuss quantum coherence effects and more generally the optical properties of ultracompact (with dimensions below the diffraction limit) hybrid structures, composed of metallic nanoparticles and a single quantum dot. The coupling between a single quantum emitter and a metallic nanoparticle can give rise to a Fano interference effect which strongly influences the quantum statistical properties of the scattered photons.