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Magnetic Field Effects in the Pseudogap Phase: A Competing Energy Gap Scenario for Precursor Superconductivity

Ying-Jer Kao·Andrew P. Iyengar·Qijin Chen·K. Levin
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Abstract

We study the sensitivity of T_c and T^* to low fields, H, within the pseudogap state using a BCS-based approach extended to arbitrary coupling. We find that T^* and T_c, which are of the same superconducting origin, have very different H dependences. This is due to the pseudogap, Δ_{pg}, which is present at the latter, but not former temperature. Our results for the coherence length ξfit well with existing experiments.We predict that very near the insulator ξwill rapidly increase.

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Ying-Jer Kao, Andrew P. Iyengar, Qijin Chen, K. Levin. 2001-09-20. Magnetic Field Effects in the Pseudogap Phase: A Competing Energy Gap Scenario for Precursor Superconductivity. https://doi.org/10.1103/physrevb.64.140505

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