Magnetic Field Dependence of Hall Coefficient in Short-Period PbTe/SnTe Superlattices

Abstract

The dependence of the Hall coefficient on magnetic field (B < 1.5 T), measured at 77 K, in short‐period (D < 40 nm), strained PbTe superlattices is analysed and interpreted. It is concluded that the superlattice is of type II. In addition to the electrons in PbTe and holes in SnTe, a third kind of charge carriers, having a high mobility, appears to take part in the conduction process. The third carriers can be both electron and hole‐like particles. Those carriers are connected with interface states which are expected to exist at the PbTe/SnTe interface. The carrier concentrations and mobilities in the bulk of the layers and at the interface are determined.

Reciprocal space maps of PbTe/SnTe superlattices

“…Mironov et al 3 have explained the anomalous behavior of the conductivity in their samples by a structural phase transition undergone by the SnTe layer. Litvinov et al 4 have used the presence of two-dimensional interface states to explain the magnetic field dependence of Hall coefficient of short-period SLs. Unfortunately, structural characterization of these samples has been almost forgotten, although many of the observed electrical properties and most of the open questions are probably related to structural details of the samples.…”

SnTe Phase Transition in Strained Superlattices PbTe/SnTe

“…In Ref. [8], it was concluded that in the PbTe/SnTe SLs, the hole concentrations in the SnTe layers were considerably smaller than those in the single films and bulk crystals of SnTe.…”

Effect of Boundary Conditions on the Interface Tamm's States

“…The existence of two-dimensional states in the PbTe/SnTe interface was proved by experiment [1]. The electron-and hole-like particles associated with interface states exhibit a high mobility and lowered concentration compared with bulk carriers.…”