An silicon nanocrystal laser

TL;DR

This paper reports the first successful room-temperature all-silicon laser utilizing silicon nanocrystals with high optical gains, achieved through innovative fabrication and feedback techniques.

Contribution

It demonstrates a novel all-silicon laser at room temperature based on silicon nanocrystals with high optical gain, using a nanoimprint-fabricated Bragg grating as a DFB cavity.

Findings

Achieved lasing action with threshold effect and spectral narrowing.

Demonstrated polarization dependence of the laser emission.

Used femtosecond optical pumping to induce lasing.

Abstract

Silicon lasers have been the most challenging element for the monolithic integrated Si photonics. Here we report the first successful all-Si laser at room temperature based on silicon nanocrystals (Si NCs) with high optical gains. The active Si NC layer was made from hydrogen silsesquioxane (HSQ) that had undergone a phase separation annealing, followed by high-pressure hydrogen passivation. Using the nanoimprint technique, a second-order Bragg grating was made on the active layer as the distributed feedback (DFB) laser cavity. This Si NC DFB laser device was optically pumped with femtosecond pulses. Criteria for lasing action, i.e., the threshold effect, the polarization dependence and the significant spectral narrowing of stimulated emission were evidently fulfilled, which indicated the realization of an all-Si laser.