Articolo in rivista, 2020, ITA, 10.1364/PRJ.393070

Unidirectional reflection from an integrated "taiji" microresonator

Calabrese, A.; Ramiro-Manzano, F.; Price, H. M.; Biasi, S.; Bernard, M.; Ghulinyan, M.; Carusotto, I; Pavesi, L.

Univ Paris, CNRS, Paris Sci & Lettres, Lab Phys,Ecole Normale Super,ENS, F-75005 Paris, France; Inst Tecnol Quim CSIC UPV, Av Naranjos, Valencia 46022, Spain; Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England; Univ Trento, Dipartimento Fis, Nanosci Lab, Via Sommar 14, I-38123 Povo, TN, Italy; Fdn Bruno Kessler, Ctr Mat & Microsyst, Via Sommar 18, I-38123 Povo, TN, Italy; Univ Trento, INO CNR BEC Ctr, Via Sommar 14, I-38123 Povo, Italy; Univ Trento, Dept Phys, Via Sommar 14, I-38123 Povo, Italy

We study light transmission and reflection from an integrated microresonator device, formed by a circular microresonator coupled to a bus waveguide, with an embedded S-shaped additional crossover waveguide element that selectively couples counter-propagating modes in a propagation-direction-dependent way. The overall shape of the device resembles a "taiji" symbol, hence its name. While Lorentz reciprocity is preserved in transmission, the peculiar geometry allows us to exploit the non-Hermitian nature of the system to obtain high-contrast unidirectional reflection with negligible reflection for light incident in one direction and a significant reflection in the opposite direction. (C) 2020 Chinese Laser Press

Photonics Research 8 (8), pp. 1333–1341

Keywords

Reciprocity; photonic device; microcavity

CNR authors

Carusotto Iacopo

CNR institutes

INO – Istituto nazionale di ottica