Dereje, Fufa (2017) Study of Effects of Magnon-Exciton Interaction on Ferromagnetism of Diluted Magnetic Semiconductors. Masters thesis, Addis Ababa University.
![[img]](http://thesisbank.jhia.ac.ke/style/images/fileicons/application_pdf.png) |
PDF (Study of Effects of Magnon-Exciton Interaction on Ferromagnetism of Diluted Magnetic Semiconductors)
Dereje, Fufa.pdf - Accepted Version Restricted to Repository staff only Download (1MB) | Request a copy |
Abstract
In this thesis the effect of exciton-magnon interaction on Diluted Magnetic Semiconductors (DMS) is theoretically studied employing quantum field theory. The double time temperature Green function technique is used to find dispersion whereby single mode magnon number is obtained from spectral density calculations. It is understood that the existence of exciton and magnon coupling increases total number of magnons which is the reason for decrease in magnetization leading to lowering of ferromagnetic transition temperature Tc. This is perhaps due to scattering of orientations of introduced magnetic spins. The disorder is attributed as enhanced by long time coupling of electron-hole pair, reducing number of holes that mediate ferromagnetism. At lower temperatures the impurity concentration, x and Tc direct relation is known to violate due to the T 1=2 containing factor dominance.
| Item Type: | Thesis (Masters) |
|---|---|
| Subjects: | Q Science > Q Science (General) Q Science > QC Physics |
| Divisions: | Africana |
| Depositing User: | Selom Ghislain |
| Date Deposited: | 04 Oct 2018 08:15 |
| Last Modified: | 04 Oct 2018 08:15 |
| URI: | http://thesisbank.jhia.ac.ke/id/eprint/5881 |
Actions (login required)
 |
View Item |