Abstract
After a brief introduction of the spin-polarized scanning tunneling microscopy (SP-STM), its measurement techniques are described based on our recent experimental results. We have observed anomalously high spin contrast for epitaxially grown Mn(001)/Fe(001) samples. This phenomenon can be attributed to a single atom or a cluster of Mn attached to the apex of the thin film Fe tip. This interpretation is supported by a recent first-principle calculation of model magnetic tips. These results stress the importance of the identification of the magnetic tip and its precise control at an atomic level for the purpose of SP-STM measurement.
