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arXiv · 0801.4611

Effective theory of fluctuating circulating currents in high-Tc cuprates

Kjetil Borkje·Asle Sudbo
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Abstract

We derive an effective dissipative quantum field theory for fluctuating orbital currents in clean $CuO_2$ sheets of high-$T_c$ cuprates, based on a three-band model. The Coulomb repulsion term between $Cu$- and $O$-sites is decoupled in terms of current operators representing horizontal and vertical parts of circulating currents within each $CuO_2$ unit cell of the lattice. The model has ordering of currents at finite temperatures. The dissipative kernel in the model is of the form $|ω|/|{\bf q}|$, indicating Landau damping. Applications of the effective theory to other models are also discussed.

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Kjetil Borkje, Asle Sudbo. 2008-01-30. Effective theory of fluctuating circulating currents in high-Tc cuprates. https://doi.org/10.1103/physrevb.77.092404

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