EXCITATION AND QUENCHING OF YB INTRA-4F-SHELL LUMINESCENCE IN INP0.93AS0.07

Photoluminescence excitation (PLE) experiments on Yb3+ in InP0.93As0.07 has been performed for the first time. The PLE spectra were measured at 4.2, 42, and 70 K. At each temperature the most efficient luminescence of Yb was achieved with the excitation wavelength tuned to an energy level located at a depth of 28 +/- 2 meV in the band gap, which we assign to an axial Yb-P3As center. It has been shown that the 4f-shell emission is thermally deactivated with a characteristic energy of 115 +/- 10 meV (190 +/- 10 meV in a reference InP:Yb sample), equal to the difference between the band gap and the F-2(5/2)-F-2(7/2) transition energy, thereby confirming dissociation of the excited state of Yb3+ by phonon absorption.