Large Magnetoresistance and Fermi Surface Topology of Sn_xPb_1-xTe Single Crystals

We have investigated the magnetotransport properties of a topological crystalline insulator, Sn_xPb_1-xTe. Resistance shows a large positive magnetoresistance that reaches a value up to 310% at H = 13 T without showing any sign of saturation. At higher fields, both longitudinal and Hall resistance show clear Shubnikov de Haas (SdH) oscillations. There exists a single oscillation frequency, f = 59 T, however, additional frequencies show up at higher tilt angles of applied field with the normal to the sample surface. We have explored the Fermi surface topology by carrying out a detailed angle dependent measurement of quantum oscillations and Berry phase calculations.