724 research outputs found
Aharonov-Bohm oscillations in the local density of states
The scattering of electrons with inhomogeneities produces modulations in the
local density of states of a metal. We show that electron interference
contributions to these modulations are affected by the magnetic field via the
Aharonov-Bohm effect. This can be exploited in a simple STM setup that serves
as an Aharonov-Bohm interferometer at the nanometer scale.Comment: 4 pages, 2 figures. v2 added reference
Antiferromagnetic and spin gap phases of the anisotropic Kondo necklace model
We have studied the effect of anisotropies on the quantum phase transition of
the Kondo necklace model in dimensions D=1, 2 and 3. Both the anisotropy
of the inter-site interaction term and anisotropy of the
on-site Kondo interaction have been included. We use a bond operator method
with constraints implemented in mean field approximation. Starting from the
paramagnetic phase we determine the critical ratio of the quantum
critical point and associated scaling exponents of the Kondo-singlet gap. We
show that in the case of easy-axis type anisotropy a qualitatively
new behavior in comparison to the conventional Kondo necklace model with
(,)=(0,1) appears. We have also obtained the antiferromagnetic
order parameter in the long range ordered phase for .Comment: 12 pages and 9 figures, to appear in PR
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