Abstract
We present evidence for a strong interaction between the conduction band and a narrow resonant band formed by nitrogen states in alloys. The interaction leads to a splitting of the conduction band into two subbands and a reduction of the fundamental band gap. An anticrossing of the extended states of the conduction band of the matrix and the localized nitrogen resonant states is used to model the interaction. Optical transitions associated with the energy minima of the two subbands and the characteristic anticrossing behavior of the transitions under applied hydrostatic pressure have been unambiguously observed using photomodulation spectroscopy. The experimental results are in excellent quantitative agreement with the model.
- Received 18 September 1998
DOI:https://doi.org/10.1103/PhysRevLett.82.1221
©1999 American Physical Society