Superconducting transition temperature and the thickness of CuO planes of NaCoOyHO

茂吉 武人*; 小林 義明*; 安井 幸夫*; 佐藤 正俊*; 加倉井 和久

Solid State Sciences, 12(5), p.656 - 659, 2010/05

https://doi.org/10.1016/j.solidstatesciences.2008.09.016

The superconductivity of NaCoOyHO appears in two regions of Co-nuclear quadrupole frequency divided by a narrow non-superconducting phase in the Tc- phase diagram. Specific heat measurements on several samples with different values distributing over both the superconducting regions and neutron inelastic experiments on aligned crystals of NaCoOyDO are performed to investigate the origin of the phase diagram. The obtained results are consistent with the singlet pairing picture.