High-magnetic-field and high-hydrostatic-pressure investigation of hydrogenic- and resonant-impurity states in<i>n</i>-type indium arsenide

Abstract

Hall-effect and transverse-magnetoresistance measurements were performed on pure n-type InAs samples (n\ensuremath{\simeq}2\ifmmode\times\else\texttimes\fi{}${10}^{16}$ ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}3}$) under magnetic fields up to 180 kG and hydrostatic pressures up to 18 kbar in the temperature range 2.7--8 K. At P13 kbar, the magnetic freezeout takes place into a shallow-donor level which shifts downward from the \ensuremath{\Gamma} conduction-band minimum with the pressure coefficient -0.077 meV/kbar. At P&gt;13 kbar, additional magnetic freezeout into a resonant-impurity level was observed. This resonant level lies at 68\ifmmode\pm\else\textpm\fi{}1 meV above the \ensuremath{\Gamma} conduction band and moves with pressure at the rate of -4 meV/kbar with respect to this minimum. An extra deepening of the shallow-donor level takes place when the pressure and the magnetic field are sufficiently high to induce the occupation of the resonant states.