Two dimensional Fermi surfaces in Kondo insulator SmB$_{6}$

Samarium hexaboride SmB$_{6}$ belongs to a class of strongly correlated heavy Fermion semiconductors, in which hybridization between itinerant electrons and localized orbitals lead to opening of a charge gap at low temperature. However, the resistivity of SmB$_{6}$ does not diverge but saturates below $\sim$ 2 Kelvin. Former studies suggested that this residual conductance is contributed by intragap states with various origins. Recent theoretical developments suggest that the particular symmetry of energy bands of SmB$_{6}$ may host a topologically non-trivial surface state, i.e., a topological Kondo insulator. To probe the Fermiology of the possible metallic surface state, we use highly sensitive torque magnetometry to detect the de Haas van Alphen (dHvA) effect due to Landau level quantization. Our detailed angular and temperature data suggest two-dimensional Fermi Surfaces lie in both crystalline (001) and (101) surface planes of SmB$_6$.