Engineering topics

Trageser, Emily

Publications and source records attributed to Trageser, Emily.

3 records

DOE OSTI2022

Demonstration of yellow (568 nm) stimulated emission from optically pumped InGaN/GaN multi-quantum wells

We demonstrate room-temperature stimulated emission at 568 nm from low dislocation density InGaN/GaN multi-quantum wells. For a 1.4 mm long and a 50 $μ$4m wide ridge bar optically pumped by a high-power pulsed laser, we observed an emission peak at 568 nm with a narrow spectral width of less than 2 nm at room temperature. The measured pumping threshold is less than 1.5 MW/cm 2 , and the polarization ratio of the emission is over 90%. In conclusion, this demonstration paves the way for the future development of electrically injected InGaN semiconductor yellow laser diodes.

36 MATERIALS SCIENCE↗

DOE OSTI2022

Green edge emitting lasers with porous GaN cladding

GaN lasers with green emission wavelength at λ = 510 nm have been fabricated using novel nano-porous GaN cladding under pulsed electrical injection. The low slope efficiency of 0.13 W/A and high threshold current density of 14 kA/cm 2 are related to a combination of poor injection efficiency and high loss, analyzed by the independent characterization methods of variable stripe length and segmented contacts. Continuous wave operation showed narrowed spectra and augmented spontaneous emission.

47 OTHER INSTRUMENTATION↗

DOE OSTI2022

Nano-porous GaN cladding and scattering loss in edge emitting laser diodes

We report continuous wave operation of electrically injected InGaN laser diodes using nano-porous GaN n-side cladding with 33% porosity. At 454 nm emission wavelength, the pulsed injection slope efficiency is 0.24 W/A with a high loss of 82 cm -1 . The considerable 60 cm -1 of excess loss of the nano-porous clad lasers is attributed to scattering at pores in unintentionally 3% porosified layers, supported by numerical modeling. Simulations comparing porous GaN cladding to AlInN cladding for lasers operating at 589 nm indicate that the porous cladding provides similar internal loss and lower thermal impedance.

36 MATERIALS SCIENCE↗