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arXiv · 1008.3532

Destruction of chain-superconductivity in YBa_2Cu_4O_8 in a weak magnetic field

A. Serafin·J. D. Fletcher·S. Adachi·N. E. Hussey·A. Carrington
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Abstract

We report measurements of the temperature dependent components of the magnetic penetration depth λ(T) in single crystal samples of YBa_2Cu_4O_8 using a radio frequency tunnel diode oscillator technique. We observe a downturn in λ(T) at low temperatures for currents flowing along the b and c axes but not along the a axis. The downturn in λ_b is suppressed by a small dc field of ~0.25 T. This and the zero field anisotropy of λ(T) likely result from proximity induced superconducting on the CuO chains, however we also discuss the possibility that a significant part of the anisotropy might originate from the CuO2 planes.

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A. Serafin, J. D. Fletcher, S. Adachi, N. E. Hussey, A. Carrington. 2010-08-20. Destruction of chain-superconductivity in YBa_2Cu_4O_8 in a weak magnetic field. https://doi.org/10.1103/physrevb.82.140506

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