TY - JOUR
T1 - Double Weyl points and Fermi arcs of topological semimetals in non-Abelian gauge potentials
AU - Lepori, L.
AU - Fulga, I. C.
AU - Trombettoni, A.
AU - Burrello, M.
N1 - [Qdev]
PY - 2016/11/28
Y1 - 2016/11/28
N2 - We study the effect of a non-Abelian SU(2) gauge potential mimicking
spin-orbit coupling on the topological semimetal induced by a magnetic
field having π flux per plaquette and acting on fermions in a
three-dimensional (3D) cubic lattice. The Abelian π -flux term gives
rise to a spectrum characterized by Weyl points. The non-Abelian term is
chosen to be gauge equivalent to both a 2D Rashba and a Dresselhaus
spin-orbit coupling. As a result of the anisotropic nature of the
coupling between spin and momentum and of the presence of a
C4 rotation symmetry, when the non-Abelian part is turned on,
the Weyl points assume a quadratic dispersion along two directions and
constitute double monopoles for the Berry curvature. We examine the main
features of this system both analytically and numerically, focusing on
its gapless surface modes, the so-called Fermi arcs. We discuss the
stability of the system under confining hard-wall and harmonic
potentials, relevant for the implementation in ultracold atom settings,
and the effect of rotation symmetry breaking.
AB - We study the effect of a non-Abelian SU(2) gauge potential mimicking
spin-orbit coupling on the topological semimetal induced by a magnetic
field having π flux per plaquette and acting on fermions in a
three-dimensional (3D) cubic lattice. The Abelian π -flux term gives
rise to a spectrum characterized by Weyl points. The non-Abelian term is
chosen to be gauge equivalent to both a 2D Rashba and a Dresselhaus
spin-orbit coupling. As a result of the anisotropic nature of the
coupling between spin and momentum and of the presence of a
C4 rotation symmetry, when the non-Abelian part is turned on,
the Weyl points assume a quadratic dispersion along two directions and
constitute double monopoles for the Berry curvature. We examine the main
features of this system both analytically and numerically, focusing on
its gapless surface modes, the so-called Fermi arcs. We discuss the
stability of the system under confining hard-wall and harmonic
potentials, relevant for the implementation in ultracold atom settings,
and the effect of rotation symmetry breaking.
U2 - 10.1103/physreva.94.053633
DO - 10.1103/physreva.94.053633
M3 - Journal article
SN - 2469-9926
VL - 94
JO - Physical Review A - Atomic, Molecular, and Optical Physics
JF - Physical Review A - Atomic, Molecular, and Optical Physics
IS - 5
M1 - 053633
ER -