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Identification of a Marginal Fermi-Liquid in Itinerant Ferromagnet CoS2

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 نشر من قبل Francisco Rivadulla Fernandez
 تاريخ النشر 2008
  مجال البحث فيزياء
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We report specific heat, resistivity and susceptibility measurements at different temperatures, magnetic fields, and pressures to provide solid evidence of CoS2 being a marginal Fermi liquid. The presence of a tricritical point in the phase diagram of the system provides an opportunity to test the spin fluctuation theory with a high limit of accuracy. A magnetic field suppresses the amplitude of the spin fluctuations and recovers conventional Fermi liquid behavior, connecting both states continuously.



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