Inherent spin-orbit locking in topological bound state in the continuum lasing

Abstract

Bound states in the continuum (BICs) are exotic optical topological singularities that defy the typical radiation within the continuum of radiative modes and carry topological polarization vortices in momentum space. Enabling ultrahigh quality factors, BICs have been applied in realizing lasing and Bose-Einstein condensation via micro-/nano- photonic structures, and their momentum-space vortex topologies have been exploited in passive systems, revealing novel spin-orbit photonic effects. However, as representative topological properties, the spin-orbit-related phenemona of BICs in active systems have not yet been explored. Here, we demonstrate the inherent spin-orbit locking in topological BIC lasing. Utilizing photonic crystal (PhC) slabs with square (C4v) and triangular (C6v) lattices, we achieve distinct spin-orbit locking combinations in topological BIC lasing of +1 and -2 topological charges. These BIC lasing profiles manifest as vortex and high-order anti-vortex polarization configurations, directly tied to the topological properties of BICs. Our experimental results directly reveal the spin-orbit locking phenomena through momentum-space spin-dependent self-interference patterns and real-space spin separations of the lasing emissions. This study not only highlights the inherent spin-orbit-locking behaviours of topological BIC lasing but also opens new possibilities for dynamically switchable orbital angular momentum (OAM) lasing by controlling photonic spin, presenting significant potential for advancements in topological photonic source applications.

References in corpus (16)

• Spin-orbit interactions of light
• Resonantly Trapped Bound State in the Continuum Laser
• Topological nature of bound states in the radiation continuum
• Lasing action in active dielectric nanoantenna arrays
• Generating optical vortex beams by momentum-space polarization vortices centered at bound states in the continuum
• Applications of Bound States in the Continuum in Photonics
• Observation of optical vortices in momentum space
• Strong light-matter interaction with self-hybridized bound states in the continuum in monolithic van der Waals metasurfaces
• Polariton Bose-Einstein condensate from a Bound State in the Continuum
• Unveiling pseudospin and angular momentum in photonic graphene
• Optically controlling the emission chirality of microlasers
• Passive Bias-Free Nonreciprocal Metasurfaces Based on Nonlinear Quasi-Bound States in the Continuum
• Strongly enhanced light-matter coupling of a monolayer WS2 from a bound state in the continuum
• Spin-Orbit-Locking Chiral Bound States in the Continuum
• Reconfigurable quantum fluid molecules of bound states in the continuum
• High topological charge lasing in quasicrystals

Cited by in corpus (3)

• Dynamically Switchable Polarization Lasing between q-BIC and Bragg Resonance Modes
• Plasmonic detection of Rashba spin-orbit coupling in monolayer transition-metal dichalcogenides
• Phase fields in momentum space of photonic crystal slabs