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arXiv · 1103.1809

Low-temperature Synthesis of FeTe0.5Se0.5 Polycrystals with a High Transport Critical Current Density

Abstract

We have prepared high-quality polycrystalline FeTe0.5Se0.5 at temperature as low as 550°C. The transport critical current density evaluated by the current-voltage characteristics is over 700 A/cm2 at 4.2 K under zero field, which is several times larger than FeTe0.5Se0.5 superconducting wires. The critical current density estimated from magneto-optical images of flux penetration is also similar to this value. The upper critical field of the polycrystalline FeTe0.5Se0.5 at T = 0 K estimated by Werthamer-Helfand-Hohenberg theory is 585 kOe, which is comparable to that of single crystals. This study gives some insight into how to improve the performance of FeTe0.5Se0.5 superconducting wires.

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BibTeXRIS

Qing-Ping Ding, Shyam Mohan, Yuji Tsuchiya, Toshihiro Taen, Yasuyuki Nakajima, Tsuyoshi Tamegai. 2011-03-09. Low-temperature Synthesis of FeTe0.5Se0.5 Polycrystals with a High Transport Critical Current Density. https://doi.org/10.1088/0953-2048%2F24%2F7%2F075025

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