Effective bond-orbital method tested on an exactly solvable model

The effective bond-orbital method (EBOM) is a computationally advantageous method, compared with multiband effective-mass methods, in situations with a degenerate band structure. We show, through comparisons with exact model calculations on superlattices, quantum wells, and localized potentials, that EBOM gives results of accuracy comparable with effective-mass theory. In EBOM there is no clear prescription how one should relate the interaction between two bond orbitals on each side of an interface to the interactions within the two materials on each side. The present study indicates that one should take the interface interaction as the geometric average of the two bulk values, not the arithmetic average that has been used so far.