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Magnetic field effects on $T_c$ and the pseudogap onset temperature in cuprate superconductors

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

We study the sensitivity of $T_c$ and the pseudogap onset temperature, $T^*$, to low fields, $H$, for cuprate superconductors, 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. The small coherence length makes $T^*$ rather insensitive to the field. However, the presence of the pseudogap at $T_c$ makes $T_c$ more sensitive to $H$. Our results for the coherence length $ξ$ fit well with existing experiments. We predict that very near the insulator $ξ$ will rapidly increase.

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Qijin Chen, Ying-Jer Kao, Andrew P. Iyengar, K. Levin. 2002-03-01. Magnetic field effects on $T_c$ and the pseudogap onset temperature in cuprate superconductors. https://doi.org/10.1142/s0217979202013869

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