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Spontaneous Vortex Phase in the Bosonic RVB Theory

Z. Y. Weng·V. N. Muthukumar
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Abstract

In the description of spin-charge separation based on the phase string theory of the t-J model, spinon excitations are vortices in the superconducting state. Thermally excited spinons destroy phase coherence, leading to a new phase characterized by the presence of free spinon vortices at temperatures, T_c<T<T_v. The temperature scale T_v at which holon condensation occurs marks the onset of pairing amplitude, and is related to the spin pseudogap temperature T^*. The phase below T_v, called the spontaneous vortex phase, shows novel transport properties before phase coherence sets in at T_c. We discuss the Nernst effect as an intrinsic characterization of such a phase, in comparison with recent experimental measurements.

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Z. Y. Weng, V. N. Muthukumar. 2002-02-06. Spontaneous Vortex Phase in the Bosonic RVB Theory. https://doi.org/10.1103/physrevb.66.094509

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