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Quantum oscillations and optical conductivity in Rashba spin-splitting BiTeI

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 نشر من قبل Catalin Martin
 تاريخ النشر 2012
  مجال البحث فيزياء
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We report the observation of Shubnikov-de Haas (SdH) oscillations in single crystals of the Rashba spin-splitting compound BiTeI, from both longitudinal ($R_{xx}(B)$) and Hall ($R_{xy}(B)$) magnetoresistance. Under magnetic field up to 65 T, we resolved unambiguously only one frequency $F = 284.3pm 1.3$ T, corresponding to a Fermi momentum $k_{F} = 0.093pm 0.002$AA$^{-1}$.The amplitude of oscillations is strongly suppressed by tilting magnetic field, suggesting a highly two-dimensional Fermi surface. Combining with optical spectroscopy, we show that quantum oscillations may be consistent with a bulk conduction band having a Rashba splitting momentum $k_{R}=0.046pm$AA$^{-1}$.

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