Unidirectional lasing via vacuum induced coherent in defective atomic lattice

TL;DR

This paper demonstrates a novel unidirectional lasing mechanism in a defective atomic lattice using vacuum induced coherence, non-Hermitian degeneracy, and spectral singularity, enhancing quantum network integration and optical transmission.

Contribution

It introduces a new scheme for unidirectional reflection lasing based on NHDSS in a defective atomic lattice, combining vacuum coherence and spectral singularity analysis.

Findings

Achieved nonreciprocal reflection and lasing oscillation in a 1D atomic lattice.

Identified conditions for NHDSS through parameter modulation and susceptibility analysis.

Enhanced optical transmission efficiency and potential for quantum network integration.

Abstract

We skillfully utilized vacuum induced coherence to amplify the probe light, and then successfully achieved both nonreciprocal reflection and lasing oscillation in a single physical system by leveraging the distributed feedback and spatial symmetry breaking effect of the one-dimensional defective atomic lattice. This innovative scheme for realizing unidirectional reflection lasing (URL) is based on both non-Hermitian degeneracy and spectral singularity (NHDSS, means $\lambda_{+}^{-1}\simeq\lambda_{-}^{-1}\rightarrow0$). Therefore, we analyze the modulation of parameters such as the lattice structure and external optical fields in this system to find NHDSS point, and further verified the conditions for its occurrence by solving the transcendental equation of susceptibility satisfying the NHDSS point, as well as analyzed its physical essence. Our mechanism is not only beneficial for the integration of photonic devices in quantum networks, but also greatly improves the efficiency of optical information transmission.