Photoluminescence measurements have been performed on cubic GaN films with carrier concentration as low as 3×10^(13) cm^(-3).From the temperature and excitation intensity dependence,the emission lines at 3.268,3....Photoluminescence measurements have been performed on cubic GaN films with carrier concentration as low as 3×10^(13) cm^(-3).From the temperature and excitation intensity dependence,the emission lines at 3.268,3.150 and 3.081 eV were assigned to the excitonic,donor-acceptor pair,and free-to-acceptor transitions,respectively.Additionally,we observed two additional emission lines at 2.926 and 2.821 eV,and suggested that they belong to donor-acceptor pair transitions.Furthermore,from the temperature dependence of integral intensities,we confirmed that three donor-acceptor pair transitions(3.150,2.926,and 2.821 eV)are from a common shallow donor to three different acceptors.The excitonic emission at 3.216 eV has a full-width-at-half-maximum value of 41 meV at room temperature,which indicates a good optical quality of our sample.展开更多
Photoluminescence spectrum of Gap ( N, Te , Zn ) under hydrostatic pressure was measured at 77K. Pressure coefficients for Te donor level as well as energy levels of excitons bound to N, NN1, NN3, and neutral donor Te...Photoluminescence spectrum of Gap ( N, Te , Zn ) under hydrostatic pressure was measured at 77K. Pressure coefficients for Te donor level as well as energy levels of excitons bound to N, NN1, NN3, and neutral donor Te were obtained. The pressure shifts of these levels were discussed. The zero phonon line of free exciton in Gap was observed for the first time.展开更多
The photoluminescence spectrum of N central cell potential bound exciton Nx as well as emission peak from deformation potential bound exclton have been observed under hydrostatic pressures. The variation of the electr...The photoluminescence spectrum of N central cell potential bound exciton Nx as well as emission peak from deformation potential bound exclton have been observed under hydrostatic pressures. The variation of the electron-phonon coupling and effective bound exciton radius with pressure is discussed.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.69776012.
文摘Photoluminescence measurements have been performed on cubic GaN films with carrier concentration as low as 3×10^(13) cm^(-3).From the temperature and excitation intensity dependence,the emission lines at 3.268,3.150 and 3.081 eV were assigned to the excitonic,donor-acceptor pair,and free-to-acceptor transitions,respectively.Additionally,we observed two additional emission lines at 2.926 and 2.821 eV,and suggested that they belong to donor-acceptor pair transitions.Furthermore,from the temperature dependence of integral intensities,we confirmed that three donor-acceptor pair transitions(3.150,2.926,and 2.821 eV)are from a common shallow donor to three different acceptors.The excitonic emission at 3.216 eV has a full-width-at-half-maximum value of 41 meV at room temperature,which indicates a good optical quality of our sample.
文摘Photoluminescence spectrum of Gap ( N, Te , Zn ) under hydrostatic pressure was measured at 77K. Pressure coefficients for Te donor level as well as energy levels of excitons bound to N, NN1, NN3, and neutral donor Te were obtained. The pressure shifts of these levels were discussed. The zero phonon line of free exciton in Gap was observed for the first time.
文摘The photoluminescence spectrum of N central cell potential bound exciton Nx as well as emission peak from deformation potential bound exclton have been observed under hydrostatic pressures. The variation of the electron-phonon coupling and effective bound exciton radius with pressure is discussed.
