THz Optical Solitons in Planarized Quantum Cascade Double Ring Lasers

Abstract

Quantum Cascade Lasers (QCL) based on cicular cavities are rapidly progressing as possible sources pf optical solitons [1], [2]. We report soliton formation in dispersion compensated THz ring QCLs [1]. The laser cavity consists of two concentric double metal ring waveguides, designed to support a symmetric and anti-symmetric super-mode where the global GVD is respectively enhanced or decreased [3](Fig. 1 a-b). The two super-modes feature different overlap factors, therefore the laser naturally selects the anti-symmetric super-mode which exhibits negative GVD.