Evaluating the performance of an AlGaN based deep ultraviolet laser diode using graded waveguide layer and graded cladding layer

To improve the output power and reduce electron leakage of a deep ultraviolet laser diode and optimize its performance,in this paper, the graded waveguide layer was first applied to a traditional AlGaN based deep ultraviolet laser diode, and four different combinations of the waveguide layer structure were simulated. Then a graded cladding layer structure with reduced thickness was added. Finally, the carrier concentration, energy band diagram, P-I curve, and optical confinement factor were numerically analysed and studied. The results demonstrate that, by using an Al-graded waveguide layer/p-cladding layer structure, the optical confinement factor of a laser diode with an emission wavelength of 267 nm, was 29.34%, and the maximum power was 89.81 mW at 100 mA current.