Please use this identifier to cite or link to this item:
|dc.title||Optical transitions and interface structure in (GaP)m/(AlP) n modulated period superlattices|
|dc.identifier.citation||Soni, R.K., Tripathy, S., Asahi, H. (2004-02). Optical transitions and interface structure in (GaP)m/(AlP) n modulated period superlattices. Physica E: Low-Dimensional Systems and Nanostructures 21 (1) : 131-142. ScholarBank@NUS Repository. https://doi.org/10.1016/j.physe.2003.10.004|
|dc.description.abstract||We have investigated optical transitions and atomically controlled interface structure in modulated period (GaP)m/(AlP)n (m, n number of monolayers) superlattices (SLs) using low-temperature photoluminescence (PL) and Raman scattering (RS) techniques. The modulated superlattices (GaP)m1(AlP)n1(GaP)m2(AlP) n2 were grown on Si-doped GaAs (001) substrate by gas source molecular beam epitaxy (m = m1+m2,n = n1+n 2,m1 > m2,n1 > n2), where total number of periods of GaP and AlP are constants, m = 13 and n = 7. By modulating the internal structure of the superlattice period strong enhancement in PL intensity was observed. In the modulated SLs, with reducing GaP layer (m1) thickness, the PL peak shows blue shift and splitting accompanied with a large intensity enhancement. We attribute enhanced strength of the optical transition to the electronic transition resulting from the disordered period in the superlattice structures. We have evaluated the Γ-X mixing factor as a function of layer thickness, from the relative oscillator strengths of the quasi-direct transitions in the modulated SLs to that of normal SL using first-order perturbation theory. Using confined optical phonons as a probe in the Raman scattering measurements, we have investigated interface structure of these modulated SLs. The confined vibrations are sensitive to the layer thickness and the presence of the atomic scale roughness at the interface. © 2003 Elsevier B.V. All rights reserved.|
|dc.contributor.department||ELECTRICAL & COMPUTER ENGINEERING|
|dc.description.sourcetitle||Physica E: Low-Dimensional Systems and Nanostructures|
|Appears in Collections:||Staff Publications|
Show simple item record
Files in This Item:
There are no files associated with this item.
checked on May 15, 2022
WEB OF SCIENCETM
checked on May 6, 2022
checked on May 12, 2022
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.