First European GaN-Based Violet Laser Diode

Abstract

We report on the realization of room temperature pulsed operation of GaInN multiple quantum well laser diodes. The devices were grown by organometallic vapor phase epitaxy on SiC substrates. Gain guided laser structures with a 8 mm wide resonator show a threshold current density of 17 kA/cm 2 . For decreasing stripe width the threshold current density increases due to decreasing overlap of electrically pumped area and the lateral extension of the optical wave. The devices were operated at temperatures up to 90 C with characteristic temperatures of 200 and 290 K for emission wavelengths of 418 and 428 nm, respectively.

Degradation Analysis of InGaN Laser Diodes

“…The LDs were grown on SiC substrates [4] (without ELO-techniques) and consist of n/p-AlGaN cladding, n/p-GaN waveguide and three In 0:10 Ga 0:9 N/GaN multiple quantum wells with a Al 0:2 Ga 0:8 N e-blocking layer. Contacts are deposited on a p-GaN contact layer and on the n-SiC backside.…”

Excitonic signature in gain and carrier induced change of refractive index spectra of (In,Al)GaN quantum well lasers

“…According to simulations for a single 2 nm QW this gain is being reached for a carrier density of 4.6ϫ 10 12 cm −2 . 11,12 The structure consists of a 900 nm thick Al 0.08 Ga 0.92 N n-cladding, 100 nm n-GaN waveguide, the active region, 20 nm AlGaN electron blocking layer, 100 nm p-GaN waveguide, 450 nm Al 0.08 Ga 0.92 N p-cladding, and a 100 nm p-GaN contact layer. It is thus natural to search for excitonic effects with the method described by Hakki and Paoli 8 which works below threshold in a carrier density regime where internal fields and the Coulomb interaction are only partially screened.…”

Laterally Coupled InGaN/GaN DFB Laser Diodes

“…A striking feature is the observed slope of the dispersion relation of --1.5 Â 10 --2 nm --1 , which is a factor of six steeper than that of the dispersion relation we obtained for optically pumped DFB lasers in the past of --2.54 Â 10 --3 nm --1 [1,2,4]. This larger slope of the refractive index dispersion in conjunction with a non-monotonic behaviour of the laser modes is attributed to incompletely screened polarisation fields in the active region of electrically pumped devices, which was also found in [11] for InGaN/GaN Fabry-Perot lasers and in [12] for InGaN/GaN LEDs. In optically pumped structures overall carrier densities are higher and therefore the internal fields are screened more efficiently.…”