Impurity effect on d-wave superconductor La1.78Sr0.22Cu1-xNixO4: A magnetic field dependent specific heat study

• Main Authors: Chun-Fu Chang, 張春富
• Other Authors: Hung-Duen Yang
• Format: Others
• Language: en_US
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/35487214698575201538

碩士 === 國立中山大學 === 物理學系 === 87 === Very recently quasiparticles in d-wave vortex state have attracted much attention. To explore this issue, magnetic field dependence of the low-temperature specific heat (LTSH) of La-1.78Sr0.22Cu1-xNixO4 is desirable to provide information about the quasiparticle electronic states of cuprates in vortex state with the presence of impurities. We found that the magnetic dependence of linear-T coefficient g of Ni-doped samples varies as Hln(1/H) rather than H1/2, consistent with the most recent theoretical approach including impurity scattering of dirty d-wave scenario. Furthermore, our results are compared with the recently proposed scaling theory.