Using photoluminescence excitation (PLE) spectroscopy we have observed the Jahn-Teller effects in vanadium-doped semi-insulating GaAs at various temperatures. The entire luminescence band ${}_{}{}^3{}_{}{}^{}$${\mathit{T}}_2$${\to }^3$${\mathit{A}}_2$ of ${\mathrm{V}}^{3+}$ ions is monitored in the PLE experiment. The observed phenomenon consists of triple-peaked PLE bands, which are attributed to the strong T⊗(${\mathit{t}}_2$+e) Jahn-Teller effects in the excited ${}_{}{}^3{}_{}{}^{}$${\mathit{T}}_1$ state of ${\mathrm{V}}^{3+}$. Detailed phonon structure of ${}_{}{}^3{}_{}{}^{}$${\mathit{A}}_2$${\to }^1$E obtained from PLE spectra is also reported. It has been found that the corresponding energy of the zero-phonon line of transition ${}_{}{}^3{}_{}{}^{}$${\mathit{A}}_2$${\to }^1$E is shifted towards lower energy by about 9 meV from temperatures of 5–300 K.

• Received 22 March 1993

DOI:https://doi.org/10.1103/PhysRevB.48.4433