We report the hydrostatic pressure dependence of the blue luminescence band observed at ∼2.8 eV in heavily magnesium-doped GaN (GaN:Mg) epilayers grown on sapphire by metalorganic chemical vapor deposition. Photoluminescence (PL) studies carried out up to 6 and 8 GPa, respectively, at room and low (10 K) temperature show that the pressure-induced energy shift of this PL band is ∼26 meV/GPa. This blueshift is about 40% less than the shift observed for the band edge in GaN. A substantially smaller pressure coefficient suggests that the 2.8 eV PL transition is associated with the recombination via deep centers.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)