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arXiv · 1308.4818

Conventional superconductivity and charge-density-wave ordering in Ba1-xNaxTi2Sb2O

Fabian von Rohr·Andreas Schilling·Reinhard Nesper·Chris Baines·Markus Bendele
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Abstract

We have investigated the low temperature physical properties of BaTi2Sb2O and Ba1-xNaxTi2Sb2O (x = 0.05, 0.1, 0.15, 0.2, 0.25, 0.3) by means of muon spin rotation (muSR) and SQUID magnetometry. Our measurements reveal the absence of magnetic ordering below TDW = 58 K in the parent compound. Therefore the phase transition at this temperature observed by magnetometry is most likely due to the formation of a charge density wave (CDW). Upon substitution of barium by sodium in Ba1-xNaxTi2Sb2O we find for x = 0.25 superconductivity with a maximum T_{c} = 5.1 K in the magnetization and a bulk T_{c,bulk} = 4.5 K in the muSR measurements. The temperature dependency of the London penetration depth lambda^-2(T) of the optimally doped compound can be well explained within a conventional weak-coupling scenario in the clean limit.

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Fabian von Rohr, Andreas Schilling, Reinhard Nesper, Chris Baines, Markus Bendele. 2013-10-10. Conventional superconductivity and charge-density-wave ordering in Ba1-xNaxTi2Sb2O. https://doi.org/10.1103/physrevb.88.140501

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