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The Berry curvature dipole in Weyl semimetal materials: an ab initio study
Noncentrosymmetric metals are anticipated to exhibit a photocurrent in
the nonlinear optical response caused by the Berry curvature dipole in momentum
space. Weyl semimetals (WSMs) are expected to be excellent candidates for
observing these nonlinear effects because they carry a large Berry curvature
concentrated in small regions, i.e., near the Weyl points. We have implemented
the semiclassical Berry curvature dipole formalism into an scheme
and investigated the second-order nonlinear response for two representative
groups of materials: the TaAs-family type-I WSMs and MoTe-family type-II
WSMs. Both types of WSMs exhibited a Berry curvature dipole, in which type-II
Weyl points are usually superior to the type-I because of the strong tilt.
Corresponding nonlinear susceptibilities in several materials promise a
nonlinear Hall effect in the field limit, which is within the
experimentally detectable range.Comment: 6 pages, 4 figures and 1 tabl
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