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arXiv · 0904.0825

New Series of Nickel-Based Pnictide Oxide Superconductors (Ni2Pn2)(Sr4Sc2O6) (Pn = P, As)

Yutaka Matsumura·Hiraku Ogino·Shigeru Horii·Yukari Katsura·Kohji Kishio·Jun-ichi Shimoyama
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Abstract

We have discovered new nickel-based pnictide oxide superconductors, (Ni2Pn2)(Sr4Sc2O6) (Pn = P, As). These compounds have a tetragonal unit cell with a space group of P4/nmm and they consist of alternate stacking of anti-fluorite Ni2Pn2 layers and K2NiF4-type Sr4Sc2O6 blocking layers. Lattice parameters were a = 4.044 A and c = 15.23 A for (Ni2P2)(Sr4Sc2O6) and a = 4.078 A and c = 15.41 A for (Ni2As2)(Sr4Sc2O6), indicating their thicker blocking layers than that of LaNiPO (c ~ 8.1 A). Both (Ni2P2)(Sr4Sc2O6) and (Ni2As2)(Sr4Sc2O6) exhibited superconductivity with zero resistivity at 3.3 K and 2.7 K, respectively. The perfect diamagnetism observed in both compounds guaranteed their bulk superconductivity.

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Yutaka Matsumura, Hiraku Ogino, Shigeru Horii, Yukari Katsura, Kohji Kishio, Jun-ichi Shimoyama. 2009-06-06. New Series of Nickel-Based Pnictide Oxide Superconductors (Ni2Pn2)(Sr4Sc2O6) (Pn = P, As). https://doi.org/10.1143/apex.2.063007

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