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Doublon formation by ions impacting a strongly correlated finite lattice system

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 Added by Michael Bonitz
 Publication date 2018
  fields Physics
and research's language is English




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Strongly correlated systems of fermions have a number of exciting collective properties. Among them, the creation of a lattice that is occupied by doublons, i.e. two quantum particles with opposite spins, offers interesting electronic properties. In the past a variety of methods have been proposed to control doublon formation, both, spatially and temporally. Here, a novel mechanism is proposed and verified by exact diagonalization and nonequilibrium Green functions simulations---fermionic doublon creation by the impact of energetic ions. We report the formation of a nonequilibrium steady state with homogeneous doublon distribution. The effect should be observable in strongly correlated solids in contact with a high-pressure plasma and in fermionic atoms in optical lattices.



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