Year: 2025
Type: article
Abstract: Anisotropy endows topological aspects in optical systems and furnishes a platform to explore non-Hermitian physics, which can be harnessed for the polarization-selective amplification of light. Here, we show a zero-threshold Raman laser can be achieved in an anisotropic optical microcavity via polarization-controlled optical pumping. A loss-gain mechanism between two polarized Stokes modes arises naturally via polarization-dependent stimulated scattering and anisotropic Raman gain of the active layered material inside the microcavity. A parity-time symmetric Hamiltonian has been proposed to explain the emergence of a single polarization mode, essential for achieving a zero-threshold lasing condition. Additionally, intensity correlation measurements of the Stokes modes validate the coherence properties of the emitted light. Our realization of the zero-threshold Raman laser in anisotropic microcavity can open up a new research direction exploring non-Hermitian and topological aspects of light in anisotropic two-dimensional materials.
Authors: A. Dhara, P. Das, D. Chakrabarty, K. Ghosh, A. Roy Chaudhuri, S. Dhara
Language: Latvian
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4406903350