ISSN:
1573-7357
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract In order to establish the existence of in-plane anisotropy of the upper critical field H c2 (θ), the out-of-plane resistivity ρ c measurements were performed on La(Sr)214 single crystals with rectangular and cylindrical shape under rotating magnetic field applied within the ab-plane. Although observed ρ c shows non-sinusoidal twofold symmetry, clear fourfold symmetry was obtained after subtracting twofold sinusoidal component in ρ c which is due to the unavoidable misalignment of the magnetic field with respect to ab-plane. H c2 (θ) is estimated from the extracted fourfold component of ρ c with the flux flow theory. Angular dependence of H c2 (θ) was well fitted by cos(4θ). Since the fourfold component of H c2 (θ) was largest at θ = nπ/2, which corresponds to the a-axis direction, the present results strongly suggest the $$d_{x^2 - y^2 } $$ type symmetry in La(Sr)214. In addition, the difference in fourfold component of H c2 at θ = nπ/2 and nπ/2+π/4 was found to increase with decreasing temperature.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1022583414539
