Collective Strain Splitting of Acceptor States in Silicon

Abstract

A splitting of the ground acceptor state in silicon due to equilibrium homogeneous strains and a corresponding transition temperature have been calculated. The equilibrium homogeneous strains are due to linear terms in the strain Hamiltonian which couple the acceptor states with the strain field. The transition temperature was found to be $N_A\times 5.6\times {10}^{-20\mathrm{}}°$K, where $N_A$ is the acceptor concentration in acceptors per cubic centimeter. For indium, concentrations as high as ${10}^{20}$ acceptors per cc $\zeta$ should be possible before Coulomb and exchange effects between acceptors are dominant.