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Magneto-thermal evidence of a partial gap at the Fermi surface of UPt_2Si_2

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 نشر من قبل Niko Johannsen
 تاريخ النشر 2008
  مجال البحث فيزياء
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Motivated by the observation of a giant Nernst effect in URu_2Si_2, the thermoelectric response of the related system UPt_2Si_2 was investigated using thermal and electric transport properties such as the Nernst and Seebeck effects, thermal conductivity, Hall effect and electrical resitivity. Unlike URu_2Si_2, UPt_2Si_2 is neither superconducting nor exhibits a ``hidden-order state. Nevertheless a pronounced Nernst effect anomaly is found to coincide with the onset of the antiferromagnetic order in UPt_2Si_2. Although the absolute values are substantially lower, its appearance and characteristics can favorably be compared to the giant Nernst effect in URu_2Si_2 indicating the common feature of a partial Fermi surface gap.

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