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Topologically Protected Wormholes in a Type-III Weyl Phase

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 Added by Christopher Sims
 Publication date 2020
  fields Physics
and research's language is English




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The observation of wormholes has proven to be difficult in the field of astrophysics. However, with the discovery of novel topological quantum materials it is possible to observe astrophysical and particle physics effects in condensed matter physics. In this work, we propose that wormholes can exist in a type-III Weyl phase. In addition, these wormholes are topologically protected, making them feasible to create and measure in condensed matter systems. Finally, several systems and experiments are put forward to confirm the existence of a type-III Weyl phase.



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90 - K. L. Zhang , Z. Song 2021
Edge states exhibit the nontrivial topology of energy band in the bulk. As localized states at boundaries, many-particle edge states may obey a special symmetry that is broken in the bulk. When local particle-particle interaction is induced, they may support a particular property. We consider an anisotropic two-dimensional Su-Schrieffer-Heeger Hubbard model and examine the appearance of $eta$-pairing edge states. In the absence of Hubbard interaction, the energy band is characterized by topologically invariant polarization in association with edge states. In the presence of on-site Hubbard interaction, $eta$-pairing edge states with an off-diagonal long-range order appear in the nontrivial topological phase, resulting in the condensation of pairs at the boundary. In addition, as Hamiltonian eigenstates, the edge states contain one paired component and one unpaired component. Neither affects the other; they act as two-fluid states. From numerical simulations of many-particle scattering processes, a clear manifestation and experimental detection scheme of topologically protected two-fluid edge states are provided.
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