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Lifshitz Transition and Superconductivity Enhancement in High Pressure $cI$16 Li

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 Added by Chia-Hui Lin
 Publication date 2013
  fields Physics
and research's language is English




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The Fermi surface topology of $cI$16 Li at high pressures is studied using a recently developed first-principles unfolding method. We find the occurrence of a Lifshitz transition at $sim$43 GPa, which explains the experimentally observed anomalous onset of the superconductivity enhancement toward lowered pressure. Furthermore we identify, in comparison with previous reports, additional nesting vectors that contribute to the $cI$16 structural stability. Our study highlights the importance of three-dimensional unfolding analyses for first-principles studies of Fermi surface topologies and instabilities in general.



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