Theory of quantum spin Hall topological lasers
Year: 2025
Authors: Heras A.M.D., Carusotto I.
Autors Affiliation: Univ Castilla La Mancha, Dept Fis, Campus Tecnol Fabr Armas, Toledo 45004, Spain; Univ Trento, CNR, INO, Pitaevskii BEC Ctr, I-38123 Trento, Italy; Univ Trento, Dipartimento Fis, I-38123 Trento, Italy.
Abstract: We theoretically investigate a quantum spin Hall topological laser formed by an array of dielectric ring resonators endowed of saturable gain. The system preserves time-reversal symmetry, the clockwise and counterclockwise modes in each ring resonator acting as two pseudospin states that experience opposite synthetic magnetic fields. We consider ring resonators featuring an internal S-shaped waveguide asymmetrically coupling the two pseudospin states. In spite of the nonmagnetic nature of the configuration, we show that an effective breaking of reciprocity is induced by the interplay of spatial parity breaking with saturable gain and a Kerr optical nonlinearity. This enables robust single-mode topological lasing even in the presence of realistic levels of backscattering.
Journal/Review: PHYSICAL REVIEW A
Volume: 112 (6) Pages from: 63536-1 to: 63536-15
More Information: A.M.d.l.H. acknowledges support from Fundacion General CSIC’s ComFuturo program, which has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie Grant Agreement No. 101034263. I.C. acknowledges support from the Provincia Autonoma di Trento; from the Q@TN Initiative; from the National Quantum Science and Technology Institute through the PNRR MUR Project No. PE0000023-NQSTI, co-funded by the European Union-NextGeneration EU.KeyWords: Electrons; StateDOI: 10.1103/mm8x-wc7p
