Stimulated emission in erbium doped silicon rich nitride waveguides

TL;DR

This paper demonstrates stimulated emission in erbium-doped silicon-rich silicon nitride waveguides, showing potential for optical amplification by optimizing silicon content.

Contribution

It reports the first observation of stimulated emission in erbium-doped silicon-rich silicon nitride waveguides with a significant inversion fraction.

Findings

50% decrease in probe absorption indicating stimulated emission

8% fraction of inverted erbium atoms achieved

Higher inversion compared to oxide systems with nanocrystals

Abstract

Stimulated emission of sensitized Erbium atoms is reported in silicon-rich silicon nitride waveguides. Visible pump and infrared probe measurements are carried out in waveguides fabricated from erbium-doped silicon rich silicon nitride. A decrease in the photoinduced absorption of the probe in the wavelength range of the erbium emission is observed and is attributed to stimulated emission from erbium atoms excited indirectly via the silicon excess in an SiNx matrix. A near 50% decrease in absorption is measured, corresponding to an 8% fraction of inverted erbium atoms. This fraction is an order of magnitude higher than that obtained in counterpart oxide systems possessing observable nanocrystals. Our results indicate that population inversion and gain at 1.54 um might be possible by optimizing the silicon excess in the SiNx matrix.