Effects of Shape and Strain Distribution of Quantum Dots on Optical Transition in the Quantum Dot Infrared Photodetectors
2008 (English)In: Nanoscale Research Letters, ISSN 1931-7573, Vol. 3, no 12, 534-539 p.Article in journal (Refereed) Published
We present a systemic theoretical study of the electronic properties of the quantum dots inserted in quantum dot infrared photodetectors (QDIPs). The strain distribution of three different shaped quantum dots (QDs) with a same ratio of the base to the vertical aspect is calculated by using the short-range valence-force-field (VFF) approach. The calculated results show that the hydrostatic strain epsilon(H) varies little with change of the shape, while the biaxial strain epsilon(B) changes a lot for different shapes of QDs. The recursion method is used to calculate the energy levels of the bound states in QDs. Compared with the strain, the shape plays a key role in the difference of electronic bound energy levels. The numerical results show that the deference of bound energy levels of lenslike InAs QD matches well with the experimental results. Moreover, the pyramid-shaped QD has the greatest difference from the measured experimental data.
Place, publisher, year, edition, pages
2008. Vol. 3, no 12, 534-539 p.
Quantum dots, PL spectrum, Strain, QDIP
IdentifiersURN: urn:nbn:se:kth:diva-24479DOI: 10.1007/s11671-008-9175-8ISI: 000260838900012ScopusID: 2-s2.0-55849092852OAI: oai:DiVA.org:kth-24479DiVA: diva2:350294
QC 201009102010-09-102010-09-102010-09-10Bibliographically approved