Effects of nitrogen on the band structure of GaNxP1-x alloys

We report that the incorporation of N in GaNxP1-x alloys (x greater than or equal to 0.43%) leads to a direct band-gap behavior of GaNP. For N concentration lower than 0.43%, a series of sharp emission lines from the various N pair centers are observed for GaNP bulk layers. With increasing N concentration higher than 0.43%, a strong photoluminescence (PL) emission from GaNP bulk layers is observed at room temperature. While the PL peak redshifts with increasing N concentration to 3.1%, the PL intensity remains as intense. Absorption measurements show a direct band-gap behavior of GaNP alloys. (C) 2000 American Institute of Physics. [S0003-6951(00)03510-5].