Short injector quantum cascade lasers

Kale J. Franz, Peter Q. Liu, James J.J. Raftery, Matthew D. Escarra, Anthony J. Hoffman, Scott Sheridan Howard, Yu Yao, Yamac Dikmelik, Xiaojun Wang, Jen Yu Fan, Jacob B. Khurgin, Claire Gmachl

Research output: Contribution to journalArticlepeer-review

12 Scopus citations

Abstract

We report our study on the effects of shortened quantum cascade (QC) laser injector regions. While conventional short-wavelength QC lasers typically have around seven or more injector region quantum wells, we investigate QC structures with three and two injector wells. Improvements in threshold currents, output powers, and wall-plug efficiencies are expected for fundamental reasons. At heat sink temperatures near 80 K, we observe threshold current densities less than 0.5 kA/cm2, nearly 4 W peak output power, and wall-plug efficiencies in excess of 20%. At room temperature, we see threshold current densities around 2.3 kA/cm2, output powers in excess of 1 W, and wall-plug efficiencies around 7.6%. We also observe new effects in midinfrared QC lasers, such as a pronounced negative differential resistance, pulse instabilities, and multiple and varied turn-off mechanisms. These effects result from the greatly abbreviated injector regions with highly discrete states.

Original languageEnglish (US)
Article number5420227
Pages (from-to)591-600
Number of pages10
JournalIEEE Journal of Quantum Electronics
Volume46
Issue number5
DOIs
StatePublished - Mar 11 2010
Externally publishedYes

Keywords

  • Midinfrared
  • Negative differential resistance
  • Quantum cascade (QC) laser
  • Short injector

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Condensed Matter Physics
  • Electrical and Electronic Engineering

Fingerprint Dive into the research topics of 'Short injector quantum cascade lasers'. Together they form a unique fingerprint.

Cite this