Terahertz beat freuquency generation from two-mode lasing operation of coupled microdisk laser

TL;DR

This paper demonstrates how coupled microdisk lasers can generate tunable terahertz radiation through two-mode lasing, with the process explained via resonant mode analysis and nonlinear effects.

Contribution

It introduces a novel approach using coupled microdisk lasers for coherent THz generation, analyzing mode transitions with a Schrödinger-Bloch model including nonlinear effects.

Findings

Two-mode lasing produces THz oscillations from mode beating.

Mode transitions are explained by resonant mode analysis.

The approach enables compact, tunable THz sources.

Abstract

We propose a coupled microdisk laser as a compact and tunable laser source for the generation of a coherent continuous wave THz radiation by photomixing. Using the Schr\"odinger-Bloch model including the nonlinear effect of active medium, we find single mode and two mode lasings depending on the pumping strength. We explain the transitions of lasing modes in terms of resonant modes which are the solutions of the Schr\"odinger-Bloch model without active medium and nonlinear interaction. In particular, a two mode lasing is shown to generate THz oscillating frequency originating from the light beating of two nearly degenerated resonant modes with different symmetries.