Electromagnetic coupling and gauge invariance in the empirical tight-binding method - art. no. 245314

We examine the requirements placed upon the Hamiltonian under the demand of gauge invariance. From these requirements we derive the gauge-invariant fo rm of the tight-binding Hamiltonian with electromagnetic coupling. In our d erivation we do not make recourse to a Peierls substitution and hence avoid introducing any ambiguities of path. Our expression transparently reduces to the familiar expression in a complete basis. We apply this Hamiltonian t o study resonant magnetotunneling spectroscopy using a simple tight-binding model.