Optical transitions of InAs/In0.36Ga0.64As/GaAs(311B) surface quantum dots clearly identified by the piezoreflectance technique

• Published in: Applied surface science Vol. 254; no. 15; pp. 4626 - 4631
• Main Authors: WANG, C, YANG, Y, CHEN, X. M, LIU, Z. L, CUI, H. Y, ZHANG, S, CHEN, X. S, LU, W
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Science 30.05.2008
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Molecular, atomic, ion, and chemical beam epitaxy; Nanoscale materials and structures: fabrication and characterization; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of bulk materials and thin films; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Physics; Piezo-, elasto-, acoustooptical, and photoacoustic effects; Piezo-, elasto-, and acoustooptical effects; photoacoustic effects; Quantum dots; Gallium arsenides; Red shift; Inorganic compounds; Semiconductor materials; Interband transitions; Quantum dots; Ternary compounds; Photoluminescence; Optical transition; Binary compounds; Spectral line shift; Piezoreflectance spectroscopy; Indium arsenides; Thickness; Energy-level transitions; Molecular beam epitaxy; Surface quantum dots; Piezoreflectance; Bilayers
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2008.01.089

The bilayer InAs/In0.36Ga0.64As/GaAs(311B) quantum dots (QDs), including one InAs buried quantum dot (BQD) layer and the other InAs surface quantum dot (SQD) layer, have been grown by molecular beam epitaxy (MBE). The optical properties of these three samples have been studied by the piezoreflectance (PzR) spectroscopy. The PzR spectra do not exhibit only the optical transitions originated from the InAs BQDs, but the features originated from the InAs SQDs. After the InAs SQDs have been removed chemically, those optical transitions from InAs SQDs have been demonstrated clearly by investigating the PzR spectra of the residual InAs BQDs in these samples. The great redshift of these interband transitions of InAs SQDs has been well discussed. Due to the suitable InAs SQD sizes and the thickness of In0.36Ga0.64As layer, the interband transition of InAs SQDs has been shifted to 1.55 mum at 77 K.