RESEARCH INTERESTS

Photonic materials: Rare-earth doped semiconductors (GaN:Er and Si:Er)

Rare earth (RE) doped semiconductors have played an important role in various optoelectronic and photonic applications, ranging from emitting elements in solid-state lasers and in phosphors for color lamps and displays to optical fiber telecommunications and to quantum information processing. Among the various rare earth elements, Er has attracted a particular attention because the ⁴I_13/2 to ⁴I_15/2 transition involving nonbonding 4f shell electrons of the Er3+ ion occurs at the technologically important wavelength of 1.54 micrometer, matching the absorption minimum of silica-based optical fibers. GaN is expected to be an ideal host material for RE doping because it is a wide and direct bandgap semiconductor, which exhibits less thermal quenching and stronger RE emission at room temperature than RE-doped Si. As a result of a continuing research effort, GaN:Er-based light emitting diodes have now been developed.

1. D. K. George, M. D. Hawkins, M. McLaren, H. X. Jiang, J. Y. Lin, J. M. Zavada, and N. Q. Vinh, Appl. Phys. Lett. 107, 171105 (2015).

2. N. Q. Vinh, H. N. Ngo, and T. Gregorkiewicz, Review paper, The proceedings of the IEEE 97.