2013 journal article

Excitonic emission dynamics in homoepitaxial AlN films studied using polarized and spatio-time-resolved cathodoluminescence measurements

APPLIED PHYSICS LETTERS, 103(14).

By: S. Chichibu*, K. Hazu*, Y. Ishikawa*, M. Tashiro*, T. Ohtomo*, K. Furusawa*, A. Uedono*, S. Mita* ...

co-author countries: Japan 🇯🇵 United States of America 🇺🇸
Source: Web Of Science
Added: August 6, 2018

Excitonic emission dynamics in homoepitaxial AlN films grown on a freestanding substrate prepared by the physical-vapor-transport method were examined. Reflecting the low threading dislocation density (<104 cm−2), room-temperature cathodoluminescence intensity images mapped at the free A-exciton energy exhibited homogeneous contrasts. Low-temperature cathodoluminescence peaks at 6.0415 and 6.0287 eV, which were polarized parallel and perpendicular, respectively, to the c-axis, exhibited identical risetimes and short lifetimes; the latter coincided with the temporal delay of neutral donor-bound exciton emissions. These results support the assumption that the two peaks originate from the recombination of free A-excitons of irreducible representations Γ1 and Γ5, respectively.