| Full text | |
| Author(s): |
Total Authors: 3
|
| Affiliation: | [1] Univ Sao Paulo, Inst Fis Sao Carlos, BR-13566590 Sao Paulo - Brazil
[2] SUNY Buffalo, Dept Phys, Buffalo, NY 14260 - USA
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | Journal of Applied Physics; v. 116, n. 19 NOV 21 2014. |
| Web of Science Citations: | 7 |
| Abstract | |
Recent advances in growth techniques have allowed the fabrication of semiconductor nanostructures with mixed wurtzite/zinc-blende crystal phases. Although the optical characterization of these polytypic structures is well reported in the literature, a deeper theoretical understanding of how crystal phase mixing and quantum confinement change the output linear light polarization is still needed. In this paper, we theoretically investigate the mixing effects of wurtzite and zinc-blende phases on the interband absorption and in the degree of light polarization of an InP polytypic superlattice. We use a single 8 x 8k.p Hamiltonian that describes both crystal phases. Quantum confinement is investigated by changing the size of the polytypic unit cell. We also include the optical confinement effect due to the dielectric mismatch between the superlattice and the vaccum and we show it to be necessary to match experimental results. Our calculations for large wurtzite concentrations and small quantum confinement explain the optical trends of recent photoluminescence excitation measurements. Furthermore, we find a high sensitivity to zinc-blende concentrations in the degree of linear polarization. This sensitivity can be reduced by increasing quantum confinement. In conclusion, our theoretical analysis provides an explanation for optical trends in InP polytypic superlattices, and shows that the interplay of crystal phase mixing and quantum confinement is an area worth exploring for light polarization engineering. (C) 2014 AIP Publishing LLC. (AU) | |
| FAPESP's process: | 12/05618-0 - Spin dynamics and spin transport in reduced dimensions: from graphene to spin lasers |
| Grantee: | Paulo Eduardo de Faria Junior |
| Support Opportunities: | Scholarships in Brazil - Doctorate |
| FAPESP's process: | 13/23393-8 - Tailoring spin-dependent and optical properties in semiconductor nanostrucures |
| Grantee: | Paulo Eduardo de Faria Junior |
| Support Opportunities: | Scholarships abroad - Research Internship - Doctorate |
| FAPESP's process: | 11/19333-4 - Tailoring spin and magnetism: electronic structure calculations |
| Grantee: | Guilherme Matos Sipahi |
| Support Opportunities: | Scholarships abroad - Research |