2016/09/12 by Somesh Chandra Ganguli, Ganguli, Somesh Chandra
Physics and Astronomy · #FOS: Physical sciences #Physics of Superconductivity and Magnetism #Superconductivity (cond-mat.supr-con)
paper · pdf · doi:10.48550/arxiv.1609.03487
openalex publication_date 2016/09/12 · openalex created_date 2022/09/05 · openalex updated_date 2026/07/28
The work presented in my doctoral thesis is an experimental investigation of\nthe nature of order to disorder transition of vortex lattice in a Type-II\nsuperconductor namely Co-intercalated 2H-NbSe2 using scanning tunnelling\nspectroscopy and complimentary ac susceptibility measurements. We have shown by\nperforming real space imaging across the magnetic field driven peak effect that\nthe vortex lattice in a 3-dimensional, weakly pinned Type-II superconductor\ndisorders through two distinct topological phase transitions. Clear evidence of\nsuperheating and supercooling with different topological property of the\nmetastable states from the actual ground states indicated the nature of both\nthe phase transformations to be of first order. We have also demonstrated the\nrole of underlying crystalline lattice symmetry by showing that it aligns the\nvortex lattice along preferential directions which is the lattice vectors of\nthe crystal lattice itself. This underlying coupling also has profound\nimplication in the order disorder transition indicating the significant role of\nvortex lattice-crystal lattice interaction in vortex phase diagram which was\nearlier being neglected.\n