Selective enhancement of 1540 nm Er3+ emission centers in Er-implanted GaNby Mg codoping

The similar to 1540 nm I-4(13/2) to I-4(15/2) Er3+ photoluminescence (PL) a nd photoluminescence excitation (PLE) spectra of Er-implanted Mg-doped GaN reveal a selective enhancement of one of the nine different Er3+ centers ob served previously in PL and PLE studies of Er-implanted undoped GaN. These Er3+ PL spectra are excited selectively by pump wavelengths that correspond to broadband, below-gap absorption bands associated with different Er3+ ce nters. In the Er-implanted, Mg-doped GaN, both the 1540 nm PL spectrum char acteristic of the so-called violet-pumped Er3+ center and the similar to 2. 8-3.4 eV (violet) PLE band that enables its selective excitation are signif icantly enhanced by Mg doping. In addition, the violet-pumped PL center dom inates the above-gap-excited Er3+ PL spectrum of Er-implanted Mg-doped GaN, whereas it was nearly unobserveable under above-gap excitation in Er-impla nted undoped GaN. These results confirm our hypothesis that appropriate cod opants can increase the efficiency of trap-mediated above-gap excitation of Er3+ emission in Er-implanted GaN. (C) 2000 American Institute of Physics. [S0003-6951(00)04917-2].