The annealed positions of ferromagnetic bonds doped into a 2D antiferromagnet: a demonstration of magnetic phase separation.
Abstract
Doping CuO2 planes with localized Oxygen holes produces magnetic interactions that, in the so--called Aharony model, can be modelled as FM bonds doped into a 2D AFM. Since mobile carriers produce spin distortions (Shraiman--Siggia dipolar backflow quasiparticles) similar to that produced by FM bonds, the simplest manner in which one can examine the effect of the magnetic interactions on the spatial distribution of such carriers is by studying the following question: What is the spatial distribution of FM bonds doped into a 2D AFM in the system's ground state? For classical spins we find that the ground state to this problem is infinitely degenerate, but that for quantum spins (viz., including zero--point spin--wave excitations) phase separated ground states are found. If the FM bond strength is less than or equal to the AFM exchange constant, we obtain the interesting result that periodic arrays of microsegregated stripes of FM bonds are the ground state.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 1997
- Bibcode:
- 1997APS..MAR.G1006S