17,462 research outputs found
Gapped spin liquid with -topological order for kagome Heisenberg model
We apply symmetric tensor network state (TNS) to study the nearest neighbor
spin-1/2 antiferromagnetic Heisenberg model on Kagome lattice. Our method keeps
track of the global and gauge symmetries in TNS update procedure and in tensor
renormalization group (TRG) calculation. We also introduce a very sensitive
probe for the gap of the ground state -- the modular matrices, which can also
determine the topological order if the ground state is gapped. We find that the
ground state of Heisenberg model on Kagome lattice is a gapped spin liquid with
the -topological order (or toric code type), which has a long
correlation length unit cell length. We justify that the TRG
method can handle very large systems with over thousands of spins. Such a long
explains the gapless behaviors observed in simulations on smaller systems
with less than 300 spins or shorter than 10 unit cell length. We also discuss
experimental implications of the topological excitations encoded in our
symmetric tensors.Comment: 10 pages, 7 figure
Anomalous Hall effect in type-I Weyl metals beyond the noncrossing approximation
We study the anomalous Hall effect (AHE) in tilted Weyl metals with Gaussian
disorder due to the crossed X and {\Psi} diagrams in this work. The importance
of such diagrams to the AHE has been demonstrated recently in 2D massive Dirac
model and Rashba ferromagnets. It was shown that the inclusion of such diagrams
dramatically changes the total AHE in such systems. In this work, we show that
the contributions from the X and {\Psi} diagrams to the AHE in tilted Weyl
metals are of the same order of the non-crossing diagram we studied in a
previous work, but with opposite sign. The total contribution of the X and
{\Psi} diagrams cancels the majority of the contribution from the non-crossing
diagram in tilted Weyl metals, similar to the 2D massive Dirac model. We also
discussed the difference of the contributions from the crossed diagrams between
2D massive Dirac model and the tilted Weyl metals. At last, we discussed the
experimental relevance of observing the AHE due to the X and {\Psi} diagrams in
type-I Weyl metal Co3Sn2S2.Comment: This paper is a sequential work of our recently published work PRB
107, 125106(2023
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