Host-isotope fine structure of the fundamental and second-harmonic transitions for theCAslocal mode in GaAs

Previously measured host-isotope fine-structure patterns of the fundamental and second-harmonic transitions associated with the local vibrational mode of ${\mathrm{C}}_{\mathrm{As}}$ in GaAs are interpreted consistently. In the analysis, quantum-mechanical perturbation theory is applied to the kinetic energy to first order in the mass differences between nearest-neighbor Ga isotopes. © 1996 The American Physical Society.