Electronic transitions of holes bound to boron acceptors in isotopically controlled diamonds

The excitation spectrum of holes bound to substitutional boron acceptors introduced into a 13C diamond is compared with that of boron acceptors in natural Type IIb diamond. While the two spectra are remarkably alike in their general features, the spectrum of the acceptors in 13C diamond is shifted to higher energies by 0.4-1.5 meV. In addition, the presence of substitutional boron relaxes the selection rule associated with translational symmetry, thus allowing the observation of the one phonon spectrum reflecting the density of states of the optical branch as well as the zone center optical phonon