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arXiv · 1210.3603

Pressure Induced Superconductivity in Ba0.5Sr0.5Fe2As2

Georgiy M. Tsoi·Walter Malone·Walter Uhoya·Jonathan E. Mitchel·Yogesh K. Vohra·Lowell E. Wenger·Athena S. Sefat·S. T . Weir
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Abstract

High-pressure electrical resistance measurements have been performed on single crystal Ba0.5Sr0.5Fe2As2 platelets to pressures of 16 GPa and temperatures down to 10 K using designer diamond anvils under quasi-hydrostatic conditions with an insulating steatite pressure medium. The resistance measurements show evidence of pressure-induced superconductivity with an onset transition temperature at ~31 K and zero resistance at ~22 K for a pressure of 3.3 GPa. The transition temperature decreases gradually with increasing in pressure before completely disappearing for pressures above 12 GPa. The present results provide experimental evidence that a solid solution of two 122-type materials, e.g., Ba1-x.SrxFe2As2 (0 < x <1), can also exhibit superconductivity under high pressure

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Georgiy M. Tsoi, Walter Malone, Walter Uhoya, Jonathan E. Mitchel, Yogesh K. Vohra, Lowell E. Wenger, Athena S. Sefat, S. T . Weir. 2012-10-12. Pressure Induced Superconductivity in Ba0.5Sr0.5Fe2As2. https://doi.org/10.1088/0953-8984%2F24%2F49%2F49570

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