Strong Intersubband Absorption by Photogenerated Carriers in Quantum Wells

E. R. Brown, K. A. McIntosh, K. B. Nichols

Research output: Contribution to journalConference articlepeer-review

Abstract

Intersubband absorption spectra in the 1O-m region are measured between 4.2 and 290 K in four n-Type GaAs/Al028Ga72As multiple-quantum-well samples. The carriers responsible for the absorption are generated by a cross-gap pump laser operating at 0.75 tim. The absorption strength per unit pump power is found to depend strongly on the background electron sheet density B' and is greatest by far in a sample having B 4x1010 cm2. By measuring the speed of response, the cause of the strong photoabsorption is found to be a long photoelectron lifetime. The sample with the strongest photoabsorption is used to make an efficient C02-laser modulator.
Original languageEnglish
Pages (from-to)260-270
Number of pages11
JournalProceedings of SPIE - The International Society for Optical Engineering
Volume1675
DOIs
StatePublished - 1992
Externally publishedYes
EventQuantum Well and Superlattice Physics IV 1992 - Somerset, United States
Duration: Mar 22 1992 → …

ASJC Scopus Subject Areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

Cite this