New Series of Nickel-Based Pnictide Oxide Superconductors (Ni2Pn2)(Sr4Sc2O6) (Pn = P, As)
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/n m m and they consist of alternate stacking of anti-fluorite Ni2Pn2 layers and K2NiF4-type Sr4Sc2O6 blocking layers. Lattice parameters were a = 4.044 Å and c = 15.23 Å for (Ni2P2)(Sr4Sc2O6) and a = 4.078 Å and c = 15.41 Å for (Ni2As2)(Sr4Sc2O6), indicating their thicker blocking layers than that of LaNiPO (c∼8.1 Å). 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.
- Publication:
-
Applied Physics Express
- Pub Date:
- June 2009
- DOI:
- 10.1143/APEX.2.063007
- arXiv:
- arXiv:0904.0825
- Bibcode:
- 2009APExp...2f3007M
- Keywords:
-
- Condensed Matter - Superconductivity
- E-Print:
- 4 pages, 3 figures, 1 table