SPECTRAL HOLE-BURNING AND UNIAXIAL-STRESS STUDY OF RADIATION-INDUCED DEFECTS IN DIAMOND

A persistent spectral hole-burning technique has been employed to inve stigate the impact of uniaxial stress on the defects created by neutro n irradiation in natural Ia-type diamond. Shifts of the spectral holes in the 649, 681, and 774 nm zero-phonon lines (ZPLs) have been measur ed. The values of the shifts, 2.2, 1.2, and 0.65 cm(-1)/kbar, obtained from these measurements have been compared with the stress shifts of the lines of defects with well-known structure. It is suggested that v acancies are present in the defect responsible for the 681 nm ZPL. A c ombination of the results of polarized luminescence and uniaxial stres s experiments leads to the conclusion of rhombic I symmetry of the def ects that give rise to the 649 and 681 nm ZPLs. (C) 1996 American Inst itute of Physics.