A study of photomodulated reflectance on staircase-like, n-doped GaAs/Al (x) Ga1-x As quantum well structures
NANOSCALE RESEARCH LETTERS, vol.7, 2012 (SCI-Expanded, Scopus)
- 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.