JQI Seminar 12/4/2017 - Arno Rauschenbeutel

Описание: "Nonreciprocal Quantum Optical Devices Based on Chiral Interaction of Confined Light with Spin-Polarized Atoms"

Speaker: Arno Rauschenbeutel, Vienna Center for Quantum Science and Technology

Abstract: The confinement of light in nanophotonic structures results in an inherent link between the light’s local polarization and its propagation direction. Remarkably, this leads to chiral, i.e., propagation-direction-dependent effects in the emission and absorption of light by quantum emitters. For example, when coupling atoms to an evanescent field, the emission rates into counter-propagating optical modes can become asymmetric [3]. In our group, we became aware of this chiral light–emitter coupling when studying the interaction of single rubidium atoms with the evanescent part of a light field that is confined by continuous total internal reflection in a whispering-gallery-mode (WGM) microresonator [4]. In the following, we employed this effect to demonstrate an integrated optical isolator [5] as well as an integrated optical circulator [6] which operate at the single-photon level and which exhibit low loss. The latter are the first two examples of a new class of nonreciprocal nanophotonic devices which exploit the chiral interaction of quantum emitters with transversally confined photons.