Questions tagged [topological-matter]
Questions about or related to topology in matter modeling.
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Gauge constraint in the definition of the Z2 invariant
Cross-posted at Physics.SE.
In Fu and Kane's paper from 2006, the authors define the $\mathbb{Z}_2$ invariant for time-reversal invariant topological insulators as an obstruction to Stoke's theorem,
$$...
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How to convert quantum anomalous Hall conductivity values from (Ohm.cm)-1 to e2/hc?
I am currently working on anomalous Hall conductivity calculations using both Wanniertools and wannier90. The output values from these calculations are provided in units of (Ohm$\cdot$cm)-1. I am ...
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What are the precise forms for the SU(2) and rotation matrices in VASP?
Some time ago, I conducted a discussion with Dr. Gui-Bin Liu on topological materials here. One relevant thing he said was:
"The format of trace.txt file is only a necessary condition to be used ...
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How to implement a Weyl semimetal in tight binding? [closed]
I want to study electronic and thermal transport properties of a Weyl semimetal. Until now, I have used only the continuum model hamiltonian ($H=k⋅σ$). As the continuum model has several limitations, ...
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Does the spin polarised DFT calculation mean broken time reversal symmetry?
Recently, I have got to learn that if time-reversal symmetry and inversion symmetry are present simultaneously in the system we have the following conditions on energy of Bloch's states:
$$E_{n,\chi }(...
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What is special about valley-focused Hamiltonians that make them give quantized/rational (valley) Chern numbers? [closed]
I have been thinking about so-called valley Chern numbers $C_v$ and associated topological phenomena. To my knowledge, they are usually applicable when inter-valley scattering is suppressed, leaving ...
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How to choose half-Brillouin-zone (HBZ) in Fukui & Hatsugai's numerical scheme for the Z2 invariant?
EDIT: Please see my first comment on this question first.
In this paper, Fukui and Hatsugai present a numerical scheme for the calculation of the $\mathbb{Z}_2$ index that uses the following ...
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Band structure of Weyl semimetal?
Weyl semimetals are topological quantum materials whose low energy excitations emerges as massles Weyl Fermions. They have a band touching point near the Fermi level called Weyl node.
What is ...
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