Stress dependence of the metal-insulator transition in doped semiconductors

The single-particle energy bands are calculated for a lattice of donors in many-valley semiconductors with a moderately strong central-cell potential using a pseudopotential constructed by the method of polarized orbitals. The variation of the metal-insulator transition with uniaxial stress is found to be in a direction opposite to that expected for effective-mass donors, as seen experimentally in phosphorus-doped silicon and arsenic-doped germanium.