Radiative recombination and ultra-long exciton photoluminescence lifetime in GaN freestanding film via two-photon excitation

  • Zhong Y
  • Wong K
  • Zhang W
 et al. 
  • 28

    Readers

    Mendeley users who have this article in their library.
  • 0

    Citations

    Citations of this article.

Abstract

We have measured the photoluminescence (PL) lifetime of a freestanding GaN film using one-photon and two-photon excitations to demonstrate the dramatic difference in exciton recombination dynamics at the surface and in the bulk. An ultralong exciton PL lifetime of 17.2 ns at 295 K is observed from a GaN freestanding film using two-photon excitation, whereas less than 100 ps lifetime is observed for one-photon excitation, suggesting that nonradiative processes from surface defects account for the short PL lifetime measured. A monotonic increase in two-photon excited PL lifetime with increasing temperature and the linear dependence of the exciton lifetime with emission wavelength show good agreement with the theoretical predictions, indicating that radiative recombination dominates for bulk excited state relaxation processes. (c) 2006 American Institute of Physics.

Author-supplied keywords

  • Exciton
  • Time resolved
  • Ultrafast processes

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

  • Yongchun Zhong

  • Kam Sing Wong

  • Weili Zhang

  • D. C. Look

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free