镍掺杂的Bi2Sr2CaCu2O8中0.2K转变的理论

Theory of the transition at 0.2 K in Ni-doped Bi2Sr2CaCu2O8.

作者信息

Joynt R

机构信息

National Center for Theoretical Sciences, P.O. Box 2-131, Hsinchu, Taiwan 300, Republic of China and and Department of Physics and Applied Superconductivity Center, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 537.

出版信息

Phys Rev Lett. 2000 Apr 24;84(17):3954-7. doi: 10.1103/PhysRevLett.84.3954.

DOI:10.1103/PhysRevLett.84.3954

PMID:11019248

Abstract

A theory is put forward that the electronic phase transition at 0.2 K in Ni-doped Bi2Sr2CaCu2O8 is a result of the formation of a spin density wave in the system of Ni impurities. The driving force for the transition is the exchange interaction between the impurity spins and the spins of the conduction electrons. This creates a small gap at two of the four nodes of the superconducting gap. The effect is to reduce the thermal conductivity by a factor of 2, as observed.

摘要

提出了一种理论，即镍掺杂的Bi2Sr2CaCu2O8中0.2K的电子相变是镍杂质系统中自旋密度波形成的结果。转变的驱动力是杂质自旋与传导电子自旋之间的交换相互作用。这在超导能隙的四个节点中的两个处产生了一个小的能隙。其效果是如所观察到的那样使热导率降低了一半。