Type:
Journal
Description:
We determine the diffusion length of excess carriers in Ga N by spatially resolved cathodoluminescence spectroscopy utilizing a single quantum well as a carrier collector or carrier sink. Monochromatic intensity profiles across the quantum well are recorded for temperatures between 10 and 300 K. A classical diffusion model accounts for the profiles acquired between 120 and 300 K, while for temperatures lower than 120 K, a quantum capture process has to be taken into account in addition. Combining the diffusion length extracted from these profiles and the effective carrier lifetime measured by time-resolved photoluminescence experiments, we deduce the carrier diffusivity as a function of temperature. The experimental values are found to be close to theoretical ones for the ambipolar diffusivity of free carriers limited only by intrinsic phonon scattering. This agreement is shown to be fortuitous. The high diffusivity at …
Publisher:
American Physical Society
Publication date:
7 Feb 2022
Biblio References:
Volume: 17 Issue: 2 Pages: 024018
Origin:
Physical Review Applied