Theory of charge and spin ordering in the nickelates - Physics ...
Theory of charge and spin ordering in the nickelates - Physics ...
Theory of charge and spin ordering in the nickelates - Physics ...
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Cubic symmetry<br />
L<strong>and</strong>au free energy<br />
F = rψ ∗· ψ + u 1 (ψ ∗· ψ) 2<br />
+u 2 |ψ · ψ| 2 + u 3<br />
<br />
(ψ · ψ) 2 +h.c. <br />
<strong>Physics</strong> <strong>of</strong> u3:<br />
fixes phase <strong>of</strong> SDW<br />
ψ = |ψ|ˆn e iθ<br />
F = constant +u 3 |ψ| 4 cos 4θ<br />
f<strong>in</strong>d θ=0 or π/4