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TT: Fachverband Tiefe Temperaturen
TT 37: Topological Semimetals - Theory (joint session TT/MA)
TT 37.3: Vortrag
Mittwoch, 3. April 2019, 10:00–10:15, H22
Chiral anomaly in Weyl semimetals within a Fermi surface harmonics approach — •Annika Johansson1,2, Jürgen Henk2, and Ingrid Mertig2,1 — 1Max Planck Institute of Microstructure Physics, Halle, Germany — 2Martin Luther University Halle-Wittenberg, Halle, Germany
In Weyl semimetals, external nonorthogonal magnetic and electric fields lead to nonconservation of the chiral charge, known as chiral anomaly [1-4].
This quantum phenomenon manifests itself in a negative longitudinal magnetoresistance.
Using a Fermi surface harmonics approach [5] for solving the semiclassical Boltzmann equation, we calculate transport properties of type-I Weyl semimetals, including influences of chiral anomaly, Lorentz force as well as momentum-dependent scattering. Respecting a modified phase-space volume, we identify additional contributions to the chiral charge conductivity which can change the sign of the magnetoresistance in systems with broken inversion symmetry. Considering momentum-dependent scattering modifies the energy-dependence of the transport properties.
On top of this, we show for TaAs that a misalignment of an applied magnetic field with the crystal axes can destroy the negative longitudinal magnetoresistance.
S. Adler, Phys. Rev. 177, 2426 (1969)
J. S. Bell and R. Jackiw, Nuovo Cimento A 60, 47 (1969)
H. B. Nielsen and M. Ninomiya, Phys. Lett. B 130, 389 (1983)
D. T. Son and B. Z. Spivak, Phys. Rev. B 88, 104412 (2013)
P. B. Allen, Phys. Rev. B 13, 1416 (1976)