New Series of Nickel-Based Pnictide Oxide Superconductors (Ni(2)Pn(2))(Sr4SC2O6) (Pn = P, As)

作者：Matsumura Yutaka; Ogino Hiraku^*; Horii Shigeru; Katsura Yukari; Kishio Kohji; Shimoyama Jun ichi

来源：Applied Physics Express, 2009, 2(6): 063007.

DOI：10.1143/APEX.2.063007

We have discovered new nickel-based pnictide oxide superconductors, (Ni(2)Pn(2))(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 Ni(2)Pn(2) layers and K2NiF4- type Sr4Sc2O6 blocking layers. Lattice parameters were a = 4.044 angstrom and c = 15.23 angstrom for (Ni2P2)(Sr4Sc2O6) and a = 4.078 angstrom and c = 15.41 angstrom for (Ni2As2)(Sr4Sc2O6), indicating their thicker blocking layers than that of LaNiPO (c similar to 8.1 angstrom). Both (Ni2P2)(Sr4Sc2O6) and (Ni2As2)(Sr4Sc2O6) exhibited superconductivity with zero resistivity at 3.3 and 2.7 K, respectively. The perfect diamagnetism observed in both compounds guaranteed their bulk superconductivity.

• 出版日期2009-6