Accession Number:

ADA433719

Title:

Ultrafast Optical Characterization of Wide Bandgap Semiconductors and Polyatomic Molecules

Descriptive Note:

Final progress rept. 1 Jul 2001-30 Sep 2004

Corporate Author:

DUKE UNIV DURHAM NC

Personal Author(s):

Report Date:

2005-05-19

Pagination or Media Count:

15.0

Abstract:

The focus of this effort was to measure the carrier dynamics in wide bandgap III-nitride materials. Measurements of carrier capture and recombination in InGaN and AlGaNGaN MQWs revealed a similar carrier capture time for both materials but a recombination time in the AlGaNGaN system at least a factor of ten faster. Studies of surface plasmonenhanced recombination rates in GaN QWs indicated an acceleration of recombination rates by a factor of 100 simply by placing a silver coating 10 nm from the QW. GaN quantum dot optical properties were studied using both ultrafast and continuous wave techniques. The interplay of carrier confinement and piezoelectric field was ascertained in the manner in which it affected the luminescence wavelength and lifetimes. Generally speaking, the larger QDs demonstrated superior optical performance, while smaller QDs behaved much like quantum wells of the same thickness.

Subject Categories:

  • Electrical and Electronic Equipment
  • Atomic and Molecular Physics and Spectroscopy
  • Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE