Dependence of the phonoionization of A+-states in Si on uniaxial pressure

Abstract

By the new technique of phonon induced conductance we have investigated the dependence on pressure of the phonoionization response of shallow A+-states in Si with superconducting Al-junctions as monochromatic phonon generators. In the case of B+ and Al+ we obtain a much more complicated behaviour than previously found for B+ with FIR-photoconductivity which may be connected with differences in coupling for short wavelength phonons. In the case of in+ on the other hand a shift to lower energies is observed for uniaxial pressure in [100]-direction whereas for pressure in [111]-direction only the signal intensity varies but not the position of the threshold.