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arXiv · 1209.5447

Ba1-xNaxTi2Sb2O (0.0 <= x <= 0.33): A Layered Titanium-based Pnictide Oxide Superconductor

Phuong Doan·Melissa Gooch·Zhongjia Tang·Bernd Lorenz·Angela Möller·Joshua Tapp·Paul C. W. Chu·Arnold M. Guloy
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Abstract

A new layered Ti-based pnictide oxide superconductor, Ba1-xNaxTi2Sb2O (0.0 <= x <= 0.33), is reported. X-ray studies reveal it crystallizes in the tetragonal CeCr2Si2C structure. The undoped parent compound, BaTi2Sb2O (P4/mmm; a=4.1196(1){\AA}; c=8.0951(2){\AA}), exhibits a CDW/SDW transition at 54K. Upon chemical doping with Na, the CDW/SDW transition is systematically suppressed and super-conductivity arises with the critical temperatures, Tc, increasing to 5.5 K. Bulk superconductivity is confirmed by resistivity, magnetic and heat capacity measurements. Like the high-Tc cuprates and the iron pnictides, superconductivity in BaTi2Sb2O arises from an ordered state. Similarities and differences to the cuprate and iron pnictide supercon-ductors are discussed.

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Phuong Doan, Melissa Gooch, Zhongjia Tang, Bernd Lorenz, Angela Möller, Joshua Tapp, Paul C. W. Chu, Arnold M. Guloy. 2012-09-24. Ba1-xNaxTi2Sb2O (0.0 <= x <= 0.33): A Layered Titanium-based Pnictide Oxide Superconductor. https://doi.org/10.1021/ja3078889

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