Spin-exchange splitting of excitons in GaN
2001 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 64, no 11Article in journal (Refereed) Published
We report on polarization-dependent photoluminescence measurements in thick GaN layers. The free-exciton emission peaks are found to appear at different energy positions in the spectra polarized perpendicular and parallel to the c, axis, In the case of E parallel toc polarization, emission from the spin-triplet state of the A exciton is observed and the singlet-triplet splitting resulting from the exchange interaction is obtained. In a highly strained layer, the splitting between the two dipole-allowed states of the B exciton is also observed. The experimental data are analyzed using an appropriate exciton Hamiltonian in a wurtzite crystal. The stress dependence of the energy splitting between the exciton states is studied and the exchange interaction constant in GaN, gamma = 0.58 +/-0.05 meV, is determined.
Place, publisher, year, edition, pages
2001. Vol. 64, no 11
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-49136DOI: 10.1103/PhysRevB.64.115201OAI: oai:DiVA.org:liu-49136DiVA: diva2:270032