Bound-to-extended state absorption in quantum wells confined byδ-like barriers

✍ Scribed by K. Durinyan; S. Petrosyan

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 217 KB
• Volume: 26
• Category: Article
• ISSN: 0749-6036
• DOI: 10.1006/spmi.1999.0774

✦ Synopsis

Within the framework of a simple envelope function and effective mass approximation, by including the spatial variation of effective mass and nonparabolicity effects, we have investigated the energy spectrum and intersubband optical absorption in a quantum well with additional thin and higher (δ-like) cladding barriers on either side of the well. The dependence of the absorption coefficient on the structure parameters, doping level, photon energy and temperature has been investigated. The absorption coefficient and spectrum strongly depend on the cladding barrier tunnel transparency. The peak absorption wavelength is shifted towards the high energies as the barrier transparency decreases. The temperature shift of the absorption peak is very small. The results are compared with experiments of Schneider et al. [7,8] taking into account the broadening induced by well width fluctuations.