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Pressure-Temperature Phase Diagram of Golden SmS

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 نشر من قبل Keiichiro Imura
 تاريخ النشر 2009
  مجال البحث فيزياء
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We measured the thermal expansion of the valence fluctuating phase of SmS (golden SmS) to construct a pressure vs temperature phase diagram. The obtained phase diagram is characterized by three lines. One is a crossover line that divides the paramagnetic phase into two regions. The other two lines correspond to a second-order Neel transition and a first-order Neel transition. The crossover line appears to emerge from a tricritical point that separates the first-order Neel transition from the second-order one. We argue that a valence jump occurs at the border of antiferromagnetism.

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