Detailed structure of the H-N-H center in GaAsyN1-y revealed by vibrational spectroscopy under uniaxial stress

The H-N-H center in GaAs1-yNy that is responsible for the band-gap shift caused by H has been studied by infrared spectroscopy in conjunction with uniaxial stress and by theory. Rich, microscopic details about its canted structure are obtained. The splitting of the infrared lines confirms the C-1h symmetry of the defect and yields a quantitative value for the canting angle of the center. The reorientation barrier of the defect is estimated from stress-induced reorientation at temperatures near 30 K to be 96 meV.