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Dissipative Berry phase effect in quantum tunneling

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 نشر من قبل Xiao-Xiao Zhang
 تاريخ النشر 2020
  مجال البحث فيزياء
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Berry phase effect plays a central role in many mesoscale condensed matter and quantum chemical systems that are naturally under the environmental influence of dissipation. We propose and microscopically derive a prototypical quantum coherent tunneling model around a monopole or conical potential intersection in order to address the intriguing but overlooked interplay between dissipation and topologically nontrivial Berry phase effect. We adopt the instanton approach with both symmetry analysis and accurate numerical solutions that consistently incorporate nonperturbative dissipation and Berry phase. It reveals a novel dissipative quantum interference phenomenon with Berry phase effect. The phase diagram of this tunneling exhibits Kramers degeneracy, nonmonotonic dependence on dissipation and a generic dissipation-driven phase transition of quantum interference, before which an unconventional dissipation-enhanced regime of quantum tunneling persists.

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