Optical Limiter Based on PT-Symmetry Breaking of Reflectionless Modes
arXiv:2306.01132 · doi:10.1364/OPTICA.497275
Abstract
The application of parity-time (PT) symmetry in optics, especially PT-symmetry breaking, has attracted considerable attention as a novel approach to controlling light propagation. Here, we report optical limiting by two coupled optical cavities with a PT-symmetric spectrum of reflectionless modes. The optical limiting is related to broken PT symmetry due to light-induced changes in one of the cavities. Our experimental implementation is a three-mirror resonator of alternating layers of ZnS and cryolite with a PT-symmetric spectral degeneracy of two reflectionless modes. The optical limiting is demonstrated by measurements of single 532-nm 6-ns laser pulses. At fluences below 10 mJ/cm2, the multilayer exhibits a flat-top passband at 532 nm. At higher fluences, laser heating combined with the thermo-optic effect in ZnS leads to cavity detuning and PT-symmetry breaking of the reflectionless modes. As a result, the entire multilayer structure quickly becomes highly reflective, protecting itself from laser-induced damage. The cavity detuning mechanism can differ at much higher limiting thresholds and include nonlinearity.
arXiv comment17 pages, 5 figures
References in corpus (11)
- Making Sense of Non-Hermitian Hamiltonians
- The physics of exceptional points
- Loss-induced suppression and revival of lasing
- Experimental Realization of a Reflective Optical Limiter
- Reflective Optical Limiter Based on Resonant Transmission
- Exceptional points of PT-symmetric reflectionless states in complex scattering systems
- Reflectionless excitation of arbitrary photonic structures: A general theory
- Asymmetric Transmission in Photonic Structures with Phase-Change Components
- Waveguide photonic limiters based on topologically protected resonant modes
- Self-Shielded Topological Receiver Protectors
- A reflective mm-wave photonic limiter