Photoluminescence spectra of the Mn 2+ d-d multiplets transitions of zinc-blende MnTe epitaxial films: laser and deuterium lamp excitation study

The luminescences of zinc-blende MnTe epitaxial films are respectively excited by a laser and deuterium lamp to study Mn2+d-d multiplets transitions. Besides the inclusion of the band gap, all other excited states related to Mn2+d-d transitions including T14(G4), T24(G4), A14[E4(G4)], T24(D4), E4(D4), and T22(I2) are observed. The shift and broadening of the T14(G4) and T24(G4) lines with increasing temperature are described by the electron–phonon coupling. Step-like energy and intensity shifts for the A14[E4(G4)], T24(D4), E4(D4), and T22(I2) transitions occur in the vicinity of the Neel point, which can be ascribed to the different spin-ordering-induced energy relaxation in ground and excited states of Mn2+d-d multiplets, and these transitions show temperature independence and weak quenching.