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Superconductivuty versus Tunneling in a Doped Antiferromagnetic Ladder

J. P. Rodriguez
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Abstract

The low-energy charge excitations of a doped antiferromagnetic ladder are modeled by a system of interacting spinless fermions that live on the same ladder. A relatively large spin gap is assumed to ``freeze out'' all spin fluctuations. We find that the formation of rung hole pairs coincides with the opening of a single-particle gap for charge excitations along chains and with the absence of coherent tunneling in between chains. We also find that such hole pairs condense into either a crystalline or superconducting state as a function of the binding energy.

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J. P. Rodriguez. 1999-03-16. Superconductivuty versus Tunneling in a Doped Antiferromagnetic Ladder. https://doi.org/10.1103/physrevb.60.1303

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