Intermetalic compounds, Strongly correlated systems
Intermetalické zlúčeniny, silne korelované systémy

Transport properties of variously doped SmB6

    SmB6 is a heavy fermion semiconductor with a narrow energy gap at the Fermi level, often denoted also as Kondo insulator, which has recently been considered to be a topological Kondo insulator, the first strongly correlated electron system to exhibit topological surface conduction states. In this contribution we have investigated the electrical transport properties of single crystalline SmB6 samples having various surfaces, of single crystalline SmB6 doped with various concentrations of lanthanum (see Fig. 1), europium, ytterbium and strontium, and of samarium deficient (i.e. doped with metal vacancies) Sm1-xB6 sintered samples with the aim to study the influence of miscellaneous doping and sample surfaces on the electronic states in the narrow energy gap of this material. The received results show rather complex resistivity vs. temperature ρ(T) and resistance vs. magnetic field ρ(H) behaviors as a function of wide range La doping and as a function of doping with different elements and vacancies. These results are discussed within the framework of the electronic structure of SmB6 observed in recent angle resolved photoemission spectroscopy as well as in other (above all transport properties) investigations, which exhibit surface electronic states in the narrow energy gap of this material.

Figure 1: Normalized temperature dependences ρ(T)/ρ(300 K) of SmB6 and Sm1-xB6. The vertical lines in panel mark the borders between different temperature regions of the characteristic ρ(T) behavior.

Philosophical Magazine, 2016,
Received 07 Jan 2016, Accepted 28 Mar 2016, Published online: 03 May 2016

S. Gabáni, M. Orendáč, G. Pristáš, E. Gažo, P. Diko, S. Piovarči, K. Flachbart (Institute of Experimental Physics, SAS, Košice)
V. Glushkov, N. Sluchanko (Prokhorov General Physics Institute, RAS, Moscow),
A. Levchenko, N. Shitsevalova (Institute for Problems of Materials Science, NASU, Kiev, Ukraine).