Сканирующая туннельная микроскопия в халькогенидных термоэлектриках (Bi, Sb)-=SUB=-2-=/SUB=-(Te, Se, S)-=SUB=-3-=/SUB=-

The morphology studies of the interlayer surface (0001) were carried out by the method of scanning tunneling microscopy in the n–Bi1.6Sb0.4Te2.94Se0.06, n- Bi1.8Sb0.2Te2.82Se0.09S0.09, p-Bi0.8Sb1.2Te2.91Se0.09 and p-Bi0.7Sb1.3Te2.91Se0.09 solid solutions. On the surface (0001), impurity and native defects were found (vacancies of tellurium, antisite defects, adatoms), formed in the compositions due to substitutions of atoms in the Bi2Te3 sublattices. The average values of HM and the standard deviations of HS in height in the distribution of atoms on the surface are determined depending on the composition of the solid solution. The effect of detected defects on the thermoelectric properties of solid solutions has been established.

Numerical simulations for ferromagnetic resonance of nano-size island structures probed by radio-frequency scanning tunneling microscopy

We numerically calculated ferromagnetic resonance (FMR) spectra taken on a single-domain nano-size ferromagnetic island structure in the configuration of radio-frequency scanning tunneling microscopy (RF-STM), where RF electromagnetic waves are introduced into the tunneling gap through the probe tip. In this scheme, near-field in-plane azimuthal RF magnetic field induces FMR of an out-of-plane magnetized island situated below the tip under the external out-of-plane magnetic field. The amount of the magnetization of the island is effectively reduced by the resonance and the reduction can be detected from the spin-polarized tunneling conductance. From the calculated spectra we found that the FMR signal becomes larger with a smaller tip-sample distance and a sharper tip. It is also revealed that the azimuthal RF magnetic field and therefore the FMR signal are enhanced when a tip is located near the edge of the island.