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Infinite critical boson non-Fermi liquid on heterostructure interfaces

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 Added by Xiao-Tian Zhang
 Publication date 2021
  fields Physics
and research's language is English




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We study the emergence of non-Fermi liquid on heterostructure interfaces where there exists an infinite number of critical boson modes in two spatial dimensions for the magnetic fluctuations. At the interface, the interfacial Dzyaloshinskii-Moriya interaction naturally emerges in the magnetic interactions due to the absence of the inversion symmetry. The interfacial Dzyaloshinskii-Moriya interaction gives rise to a degenerate contour for the low-energy bosonic modes in the momentum space, which simultaneously becomes critical approaching the magnetic phase transition. The presence of the critical boson contour leads to a divergence in the dynamical magnetic susceptibility. The itinerant electrons are scattered by the critical boson contour and develop non-Fermi liquid behaviors. With a self-consistent renormalization calculation, we uncover a prominent non-Fermi liquid behavior in the resistivity with a characteristic temperature scaling power. These results set another possibility for the boson-fermion coupled problems and the fermion criticality.



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