How Much Phase Coherence Does a Pseudogap Need?

Paul E. Lammert; Daniel S. Rokhsar

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arXiv · cond-mat/0108146

How Much Phase Coherence Does a Pseudogap Need?

Paul E. Lammert·Daniel S. Rokhsar

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Abstract

It has been suggested that the ``pseudogap'' regime in cuprate superconductors, extending up to hudreds of degrees into the normal phase, reflects an incoherent d-wave pairing, with local superconducting order coherent over a finite length scale $ξ$, insufficient to establish superconductivity. We calculate the single-particle spectral density in such a state from a minimal phenomenological disordered BCS model. When the phase-coherence length exceeds the Cooper pair size, a clear pseudogap appears. The pseudogap regime, however, is found only over a relatively narrow range of phase stiffnesses, hence is not expected to extend more than about 20% above $T_c$.

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Paul E. Lammert, Daniel S. Rokhsar. 2001-08-08. How Much Phase Coherence Does a Pseudogap Need?. https://arxiv.org/abs/cond-mat/0108146

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