Transport and Magnetic Properties of Single-Crystal Lu(Ni_1- xCo_x)_2B_2C (x = 0 - 0.09)
Abstract
In fields greater than approximately 1 kG (H_crit), the vortex lattice of LuNi_2B_2C has a four-fold (square) symmetry. Weaker applied fields result in a triangular vortex lattice. Theoretical models of this phase transition involve both the coherence length and the mean free path. Small amounts of cobalt substitution allow for the careful adjustment of both quantities, and provides a practical method for increasing H_crit. Results of resistivity and dc-magnetic susceptibility measurements are presented for single-crystal samples of Lu(Ni_1-xCo_x)_2B_2C (x = 0 - 0.09). Residual resistivities (ρ_0) are a factor of five smaller than values obtained for polycrystalline samples. We find that (ρ_0) increases by 1.5 μΩcm per percent Co. Implications of these results for values of the hex-to-square vortex lattice transition will be discussed. Ames Laboratory is operated for the U.S. Department of Energy by Iowa State University under Contract No. W-7405-Eng-82.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 1998
- Bibcode:
- 1998APS..MAR.X3709C