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Mater Sci Nanotechnol 2017
Volume 1 Issue 3
Magnetic Materials 2017
Page 92
October 09-10, 2017 London, UK
International Conference on
Magnetic phase diagram of spatially anisotropic
frustrated two-dimensional antiferromagnet
Vladimir Ilkovic
Bogoliubov Laboratory of Theoretical Physics JINR, Russian Federation
T
he new magnetic materials such as the layered oxide
high-temperature superconductor can be well described
by the Heisenberg spin model with nearest-neighbor (NN)
antiferromagnetic coupling
J
1
and next-nearest-neighbor (NNN)
antiferromagnetic coupling
J
2
. It is now well accepted that the
model
J
1
--
J
2
exhibits two phases displaying magnetic order at
small
J
2
, separated by an intermediate paramagnetic phase in
the interval
J
c1
<
J
2
<
J
c2
. The ground state for
J
2
<
J
c1
exhibits Neél
magnetic order, whereas for
J
2
>
J
c1
it exhibits collinear stripe
order. A generalization of the frustrated
J
1
-
J
2
model is the
J
1
x
--
J
1
y
-
-
J
2
model where
J
1
y
is the directional anisotropy parameter. The
nearest-neighbor bonds have different strength
J
1
x
and
J
1
y
in the x
and y directions, respectively. The effect of the coupling
J
1
y
on the
Neél and stripe states is investigated. Our aim here is to further
the study of this model by using the quantum many-body Green
function method. It has been applied successfully to calculate
with high accuracy the properties of many lattice quantum spin
systems.
vilko@theor.jinr.ruMaterials Science and Nanotechnology