Study of magnetic vortex lattice in noncentrosymmetric superconductors using small angle neutron scattering

• Applicant: Dr. Moumita Naskar
• Subject Area: Experimental Condensed Matter Physics
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 540160192

Superconductors with a noncentrosymmetric structure possess unique characteristics. The absence of inversion symmetry introduces an antisymmetric spin-orbit coupling (ASOC), which lifts the original conduction electron spin degeneracy at the Fermi level, resulting in the possible superconducting pair mixing phenomenon. There is an appreciable extent of singlet and triplet spin mixing, leading to the opening of different types of superconducting gaps in the systems. It has been found that the superconducting order parameter consisting of an admixture of spin-singlet and spin-triplet strongly affects the electronic states around the vortex core. Small angle neutron scattering (SANS) is one of the powerful tools to probe the unusual behaviour of the vortex lattice in noncentrosymmetric superconductors. From that, one can able to measure the field and temperature dependence of the VL form factor. That can allow us to investigate the gap structure of the superconductors. The main objective of the project is to explore the characteristics of the vortex lattice in noncentrosymmetric superconductors such as YPtBi, LuPtBi and NbReSi using small-angle neutron scattering. The aim is to identify qualitative distinctions arising from both the absence of inversion symmetry and the singlet-triplet properties of the order parameter.

• DFG Programme: WBP Position