• Corpus ID: 238531634

Fermi surface expansion above critical temperature in a Hund ferromagnet

  title={Fermi surface expansion above critical temperature in a Hund ferromagnet},
  author={Yusuke Nomura and Shiro Sakai and Ryotaro Arita},
Using a cluster extension of the dynamical mean-field theory, we show that strongly correlated metals subject to Hund’s physics exhibit significant electronic structure modulations above magnetic transition temperatures. In particular, in a ferromagnet having a large local moment due to Hund’s coupling (Hund’s ferromagnet), the Fermi surface expands even above the Curie temperature (Tc) as if the spin polarization occurred. Behind this phenomenon, effective “Hund’s physics” works in momentum… 

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