The optical Hall effect

ABSTRACT 1 Introduction The electrical Hall effect, which has been observed by E. H. Hall in the late 70's of the 19th century, has become the standard technique for the electri-cal characterization of free charge carrier properties in semiconductors [1]. This technique, however, requires electrical contacts and known current paths, which ex-cludes application to complex heterostructures and nano-structured materials. For example, the true free charge car-rier properties can be obscured by space charge regions caused by the contact potentials of the electrical contacts. Furthermore, it is often difficult to determine the exact car-rier path within the sample such that the free charge carrier concentrations and mobilities determined for a complex layered sample cannot be assigned separately to the indi-vidual sample constituents.