InGaN laser diodes with reduced AlGaN cladding thickness fabricated on GaN plasmonic substrate.

We demonstrate InGaN laser diodes with substantially reduced thickness of their bottom AlGaN cladding grown on plasmonic GaN substrate. The electron concentration in plasmonic substrate grown by ammonothermal method was of the order of 1020 cm-3, which corresponds to the refractive index reduction by 0.7% when comparing to undoped GaN. We were able to reduce the thickness of AlGaN bottom claddings from the initial 800 nm down to 400 nm without any worsening of laser threshold current or near-field patterns. The results are in agreement with the optical modeling of the InGaN laser diode structure fabricated on plasmonic GaN substrate. [ABSTRACT FROM AUTHOR]