Abstract
Raman spectroscopy has been used to study the lattice properties of plasma-assisted molecular beam epitaxy grown GaN:Mn layers (0–18% Mn). Raman spectra corresponding to the intrinsic GaN layers demonstrate three Raman active excitations at 144, 570 and 729.2
cm
−1, identified as
E
2
L
,
E
2
H
and A
1(LO) respectively. The Mn-doped GaN layers exhibit additional excitations attributed to defect-activated Raman scattering and Mn
m
–N (
m =1–4) related frequency modes in the vicinity of
E
2
H
mode. Subsequently, detailed X-ray diffraction measurements have revealed the coexistence of cubic phases in the predominantly hexagonal GaN lattice.