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تسجيل مستخدم جديدLarge magnetoresistance and Fermi surface study of Sb$_2$Se$_2$Te single crystal
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We have studied the magnetotransport properties of a Sb$_2$Se$_2$Te single crystal. Magnetoresistance (MR) is maximum when the magnetic field is perpendicular to the sample surface and reaches to a value of 1100% at $B$=31 T with no sign of saturation. MR shows Shubnikov de Haas (SdH) oscillations above $B$=15 T. The frequency spectrum of SdH oscillations consists of three distinct peaks at $alpha$=32 T, $beta$=80 T and $gamma$=117 T indicating the presence of three Fermi surface pockets. Among these frequencies, $beta$ is the prominent peak in the frequency spectrum of SdH oscillations measured at different tilt angles of the sample with respect to the magnetic field. From the angle dependence $beta$ and Berry phase calculations, we have confirmed the trivial topology of the $beta$-pocket. The cyclotron masses of charge carriers, obtained by using the Lifshitz-Kosevich formula, are found to be $m^{*}_{beta}=0.16m_o$ and $m^{*}_{gamma}=0.63m_o$ for the $beta$ and $gamma$ bands respectively. Large MR of Sb$_2$Se$_2$Te is suitable for utilization in electronic instruments such as a computer hard disc, high field magnetic sensors, and memory devices.
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