Band anticrossing in III-N-V alloys

Recent high hydrostatic pressure experiments have shown that incorporation of small amounts of nitrogen into conventional III-V compounds to form III- N-V alloys leads to splitting of the con duction band into two subbands. Th e downward shift of the lower subband edge is responsible for the observed, large reduction of the fundamental band gaps in III-N-V alloys. The observ ed effects were explained by an anticrossing interaction between the conduc tion band states close to the center of the Brillouin zone and localized ni trogen states, The interaction leads to a change in the nature of the funda mental from the indirect gap in GaP to a direct gap in GaNP. The prediction s of the band anticrossing model of enlarged electron effective mass and en hanced donor activation efficiency were confirmed by experiments in GaInNAs alloys.