Influence of Thickness on Orientational Dependence of Critical Current Density of NbTi Thin Films
The influence of thickness on the orientational dependence of critical current density J c of NbTi thin films has been studied experimentally. The thickness, d, of the films investigated are 26 mn, 35 nm, 50 nm, and 120 nm. Measurements of J c as a function of the amplitude and orientation of the magnetic field B with respect to the film plane are performed at 4.2 K. It is found that the orientational dependence of J c clearly changes from a simple behavior to a more complex one with increasing the thickness of the films. The ratio of J c for perpendicular and parallel film orientation is empirically seen to increase as d 1/2 . The parallel field dependence of J c is qualitatively described using the theoretical expressions derived by Mawatari and Yamafuji.
KeywordsCritical Current Density High Magnetic Field Multilayer Film Film Plane Theoretical Expression
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