High power (60 mW) GaSb-based 1.9 μm superluminescent diode with cavity suppression element

The characteristics and the fabrication of a 1.9 μm superluminescent diode utilizing a cavity suppression element are reported. The strong suppression of reflections allows the device to reach high gain without any sign of lasing modes. The high gain enables strong amplified spontaneous emission and output power up to 60 mW in a single transverse mode. At high gain, the spectrum is centered around 1.9 μm and the full width at half maximum is as large as 60 nm. The power and spectral characteristics pave the way for demonstrating compact and efficient light sources for spectroscopy. In particular, the light source meets requirements for coupling to silicon waveguides and fills a need for leveraging to mid-IR applications photonics integration circuit concepts exploiting hybrid integration to silicon technology.