A study of photomodulated reflectance on staircase-like, n-doped GaAs/Al (x) Ga1-x As quantum well structures

DÖNMEZ Ö., NUTKU F., EROL A., Arikan C. M., ERGÜN Y.

NANOSCALE RESEARCH LETTERS, vol.7, 2012 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 7
  • Publication Date: 2012
  • Doi Number: 10.1186/1556-276x-7-622
  • Journal Name: NANOSCALE RESEARCH LETTERS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Keywords: Photomodulated reflectance, Quantum well infrared photodetectors (QWIP), Aspnes' third derivative form, Excitonic levels, TRANSFER-MATRIX METHOD, INFRARED PHOTODETECTORS, SCHRODINGER-EQUATION
  • Anadolu University Affiliated: Yes

Abstract

In this study, photomodulated reflectance (PR) technique was employed on two different quantum well infrared photodetector (QWIP) structures, which consist of n-doped GaAs quantum wells (QWs) between undoped Al (x) Ga1-x As barriers with three different x compositions. Therefore, the barrier profile is in the form of a staircase-like barrier. The main difference between the two structures is the doping profile and the doping concentration of the QWs. PR spectra were taken at room temperature using a He-Ne laser as a modulation source and a broadband tungsten halogen lamp as a probe light. The PR spectra were analyzed using Aspnes' third derivative functional form.