ELECTRONIC SURFACE-STATES IN A SEMIINFINITE EFFECTIVE-MASS SUPERLATTICE

The electronic structure of a semi-infinite effective-mass superlattic e (EMSL) being in contact with a substrate is investigated taking into account the effect of the EMSL surface (i.e. the EMSL/substrate bound ary). In particular, the influence of the EMSL bulk and surface parame ters on the existence, energy position within the minigap, and localiz ation properties of surface states is studied for different EMSL termi nating layers. Additionally, the effect of a (small) conduction-band e dge discontinuity between the EMSL layers on the surface electronic st ructure is examined and the maintenance of the basic features of the s urface-state energy curve is found. The usefulness of the obtained res ults for the possible device applications of the EMSL is pointed out.