• M K Mukhopadhyay

      Articles written in Pramana – Journal of Physics

    • Two-dimensional magnetic ordering in a multilayer structure

      M K Mukhopadhyay M K Sanyal

      More Details Abstract Fulltext PDF

      The effect of confinement from one, two or from all three directions on magnetic ordering has remained an active field of research for almost 100 years. The role of dipolar interactions and anistropy are important to obtain, the otherwise forbidden, ferromagnetic ordering at finite temperature for ions arranged in two-dimensional (2D) arrays (monlayers). We have demonstrated that conventional low-temperature magnetometry and polarized neutron scattering measurements can be performed to study short-range ferromagnetic ordering of in-plane spins in 2D systems using a multilayer stack of non-interacting monolayers of gadolinium ions formed by Langmuir-Blodgett (LB) technique. The spontaneous magnetization could not be detected in the heterogeneous magnetic phase observed here and the saturation value of the net magnetization was found to depend on the sample temperature and applied magnetic field. The net magnetization rises exponentially with lowering temperature and then reaches saturation following a T ln(βT) dependence. The T ln (βT) dependence of magnetization has been predicted from spinwave theory of 2D in-plane spin system with ferromagnetic interaction. The experimental findings reported here could be explained by extending this theory to a temperature domain of βT<1.

  • Pramana – Journal of Physics | News

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2021-2022 Indian Academy of Sciences, Bengaluru.