P-31 ELECTRON-NUCLEAR DOUBLE-RESONANCE OF THE P(IN) ANTISITE IN INPZN DETECTED VIA LUMINESCENCE

Optically detected electron-nuclear double resonance (ODENDOR) has been observed via photoluminescence from the first-neighbor P-31 shell of the phosphorus antisite in zinc-doped InP. Analysis of the ENDOR data confirms a tetrahedral arrangement of P-31 nuclei. The hyperfine interaction for each of these nuclei is axial with \A parallel-to\ /h = 368.0 +/- 0.5 MHz and \ A perpendicular-to\ Ih = 247.8 +/- 0.5 MHz. These parameters are slightly different from those reported by Jeon et al. [Phys. Rev. B 36, 1324 (1987)]. A shift of the ENDOR frequencies correlated with a change in the central nuclear-spin state has also been observed. We have been able to account for this shift with a perturbation treatment in which the electronic spin and central nuclear spin are treated exactly and a neighboring nuclear spin provides the perturbation. The best ENDOR signals are obtained with low optical-excitation-power density (approximately 0.1 W/cm2) and low microwave modulation frequency (17 Hz). These conditions emphasize the contributions to the optically detected magnetic-resonance signal from distant donor-acceptor pairs.