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Hysteretic Magnetotransport in SmB6 at Low Magnetic Fields

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 نشر من قبل Yun Suk Eo
 تاريخ النشر 2014
  مجال البحث فيزياء
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Utilizing Corbino disc structures, we have examined the magnetic field response of resistivity for the surface states of SmB6 on different crystalline surfaces at low temperatures. Our results reveal a hysteretic behavior whose magnitude depends on the magnetic field sweep rate and temperature. Although this feature becomes smaller when the field sweep is slower, a complete elimination or saturation is not observed in our slowest sweep-rate measurements, which is much slower than a typical magnetotransport trace. These observations cannot be explained by quantum interference corrections such as weak anti-localization. Instead, they are consistent with behaviors of glassy surface magnetic ordering, whose magnetic origin is most likely from samarium oxide (Sm2O3) forming on the surface during exposure to ambient conditions.



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