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Journal of Applied Mathematics and Statistical Applications | Volume: 1
August 23-24, 2018 | London, UK
Applied Physics
3
rd
International Conference on
Local broken symmetry and spin transport in the frustrated two-dimensional model
Leonardo dos Santos Lima
Centro Federal de Educação Tecnológica de Minas Gerais, Brazil
T
he local spontaneous symmetry breaking is a
general phenomena in condensed matter physics.
It is characterized by the fact that the action has a local
symmetry but the quantum theory, instead of having a
unique vacuum state which respects this symmetry, has a
family of degenerate vacua that transform into each other
under the action of the symmetry group. A simple example
is given by a ferromagnetic model in which the action
governing its microscopic dynamics is invariant under spatial
rotations. A kind of local gauge invariance or spontaneous
breaking of U(1) gauge symmetry is realized in nature in the
phenomenon of superconductivity. We have proposed the
Meissner mechanism for the spin supercurrent in quantum
spin systems. Besides, we study the behavior of the AC spin
conductivity in neighborhood of quantum phase transition
in a frustrated spin model such as the antiferromagnet in
the compass lattice with single ion anisotropy at T=0. Our
results show the curve of conductivity varying strongly
with the behavior of the critical anisotropy Dc and J.
e:
lslima7@yahoo.com.br