%0 Journal Article
%T Orbital symmetry of a triplet pairing in a heavy Fermion superconductor UPt_3
%A Kazushige Machida
%A Tsutomu Nishira
%A Tetsuo Ohmi
%J Physics
%D 1999
%I arXiv
%R 10.1016/S0921-4526(99)00809-1
%X The orbital symmetry of the superconducting order parameter in UPt_3 is identified by evaluating the directionally dependent thermalconductivity and ultrasound attenuation in the clean limit and compared with the existing data for both basal plane and the c-axis of a hexagonal crystal. The resulting two component orbital part expressed by (\lambda_x(k), \lambda_y(k)) is combined with the previously determined triplet spin part, leading to clean limit and compared with the existing data for both basal plane and the c-axis of a hexagonal crystal. The resulting two component orbital part expressed by (\lambda_x(k), \lambda_y(k)) is combined with the previously determined triplet spin part, leading to the order parameter of either the non-unitary bipolar state of the form: d(k) = b \lambda_x(k) + i j \lambda_y(k) or the unitary planar state of the form: d(k) = b \lambda_x(k) + j \lambda_y(k) where b \perp j = c, or a with the hexagonal unit vectors a, b and c. The d vector is rotatable in the plane spanned by a and c perpendicular to b under weak applied c-axis field because of the weak spin orbit coupling. Experiments are proposed to distinguish between the equally possible these states.
%U http://arxiv.org/abs/cond-mat/9906105v1