Enhancement of the Superconducting Transition Temperature under Pressure in Rare-Earth Doped Ca$_{1-x}$La$_x$Fe$_2$As$_2$ (x=0.27)

Swee K. Goh; Lina E. Klintberg; J. M. Silver; F. M. Grosche; S. R. Saha; T. Drye; J. Paglione; Mike Sutherland

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arXiv · 1107.0689

Enhancement of the Superconducting Transition Temperature under Pressure in Rare-Earth Doped Ca$_{1-x}$La$_x$Fe$_2$As$_2$ (x=0.27)

Swee K. Goh·Lina E. Klintberg·J. M. Silver·F. M. Grosche·S. R. Saha·T. Drye·J. Paglione·Mike Sutherland

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Abstract

We report measurements of the pressure dependence of the superconducting transition temperature T_c in single crystal samples of the rare-earth doped superconductor Ca$_{0.73}$La$_{0.27}$Fe$_2$As$_2$. We track T_c with two techniques, via in-plane resistivity measurements and with a resonant tunnel diode oscillator circuit which is sensitive to the skin depth. We show that initially T_c rises steeply with pressure, forming a superconducting dome with a maximum T_c of ~44 K at 20 kbar. We discuss this observation in the context of other electron-doped iron pnictide superconductors, and conclude that the application of pressure offers an independent way to tune T_c in this system.

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Swee K. Goh, Lina E. Klintberg, J. M. Silver, F. M. Grosche, S. R. Saha, T. Drye, J. Paglione, Mike Sutherland. 2011-07-04. Enhancement of the Superconducting Transition Temperature under Pressure in Rare-Earth Doped Ca$_{1-x}$La$_x$Fe$_2$As$_2$ (x=0.27). https://arxiv.org/abs/1107.0689

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