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Angular Dependence of C-Axis Magnetoresistance in Bi-2212 Single Crystals With Columnar Defects

N. Morozov·L. N. Bulaevskii·M. P. Maley·J. Y. Coulter·A. E. Koshelev·T. -W. Li
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Abstract

We measured the angular dependence of the c-axis magnetoresistance rho_c(B) of Bi-2212 irradiated with heavy ions. At temperatures near 68 K the scaling of rho_c(B) with the c-axis magnetic field component B_perp is broken and the in-plane field, B_parallel, affects rho_c. At this temperature, at a specific field B_cr \approx B_Phi/2, magnetoresistance becomes independent of field orientation. This crossing point allows us to estimate the correlation length L of pancake positions along the c axis. We find L/s is about 100 at B=B_cr, where s is the interlayer spacing. This provides evidence of strong enhancement of pancake alignment in the vortex liquid in crystals with columnar defects.

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N. Morozov, L. N. Bulaevskii, M. P. Maley, J. Y. Coulter, A. E. Koshelev, T. -W. Li. 1999-03-05. Angular Dependence of C-Axis Magnetoresistance in Bi-2212 Single Crystals With Columnar Defects. https://doi.org/10.1103/physrevb.60.96

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