Magnetic anomalies in La1.85Sr0.15CuO4 crystals under tilted fields

Magnetization curves of La1.85Sr0.15CuO4 in fields slightly tilted from the ab plane exhibit an additional magnetization peak (AMP) in between the well-known first and second magnetization peaks. Measurements of the induction vector versus field reveals flux rotation from the ab plane towards the direction of the external field, beginning at the onset of the AMP. Characterization of the AMP and flux rotation as a function of temperature, time and tilting angle, shows a strong correlation between the two phenomena. This correlation is explained by considering variations in the magnetization caused by a tilt of the current flow plane associated with the flux rotation. Simulations of the magnetization curves based on the proposed model agree well with the experimental results. (c) 2007 Elsevier B.V. All rights reserved.