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Spin correlations in the algebraic spin liquid - implications for high Tc superconductors

Walter Rantner·Xiao-Gang Wen
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Abstract

We propose that underdoped high $T_c$ superconductors are described by an algebraic spin liquid (ASL) at high energies, which undergoes a spin-charge recombination transition at low energies. The spin correlation in the ASL is calculated via its effective theory - a system of massless Dirac fermions coupled to a U(1) gauge field. We find that without fine tuning any parameters the gauge interaction strongly enhances the staggered spin correlation even in the presence of a large single particle pseudo-gap. This allows us to show that the ASL plus spin-charge recombination picture can explain many highly unusual properties of underdoped high $T_c$ superconductors.

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Walter Rantner, Xiao-Gang Wen. 2002-01-28. Spin correlations in the algebraic spin liquid - implications for high Tc superconductors. https://doi.org/10.1103/physrevb.66.144501

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