Guo Z P, Zhao Y G, Zhang W Y, Cui L, Guo S M, Luo L B
Department of Physics, Tsinghua University, Beijing 100084, People's Republic of China. Department of Physics, Yanbian University, Yanji 133002, People's Republic of China.
J Phys Condens Matter. 2006 May 3;18(17):4381-8. doi: 10.1088/0953-8984/18/17/023. Epub 2006 Apr 13.
The effects of doping with magnetic Mn ions or nonmagnetic Ga ions on the structural, electrical transport and magnetic properties of Na(0.75)CoO(2) have been investigated. It has been found that the lattice parameter c of the samples increases with Ga or Mn ion doping. Ga doping raises the electrical resistivity of Na(0.75)CoO(2), but the metallic conducting behaviour of the compound has not been influenced. In contrast, 5% Mn doping leads to a metal-insulator transition at low temperatures in Na(0.75)Co(1-y)Mn(y)O(2). The susceptibility of the Ga doped sample shows strong magnetic field dependence, while the susceptibility of the Mn doped samples is not very sensitive to the magnetic field. This work implies that magnetic interaction plays an important role in Na(x)CoO(2).
研究了用磁性锰离子或非磁性镓离子掺杂对Na(0.75)CoO(2)的结构、电输运和磁性的影响。发现样品的晶格参数c随镓或锰离子掺杂而增加。镓掺杂提高了Na(0.75)CoO(2)的电阻率，但该化合物的金属导电行为未受影响。相比之下，5%的锰掺杂导致Na(0.75)Co(1-y)Mn(y)O(2)在低温下发生金属-绝缘体转变。镓掺杂样品的磁化率表现出强烈的磁场依赖性，而锰掺杂样品的磁化率对磁场不太敏感。这项工作表明磁相互作用在Na(x)CoO(2)中起着重要作用。
