Karthika Kariattukarakaran Thilakan

I hold an Integrated Master`s in Physics from Central University of Tamil Nadu, India. My master`s thesis was focused on elucidating the structural and magnetic properties of multiferroic materials.

My project within SwedNess at the Department of Earth Sciences in Uppsala University involves the study of magnetic order/disorder phenomena and structure-properties relationships in quasicrystals (QCs) and approximant crystals (ACs) using neutrons, X-rays, optical photons and pressure as probing tools. QCs, owing to their quasiperiodic nature are expected to show novel magnetic properties different from the periodic crystals. ACs are periodic crystals having atomic clusters and chemical composition close to their related QCs. In this research, Tsai-type QCs and ACs in the systems RE-Au-E (RE- Lanthanides, Y, Sc, Ca and E- Si, Ge, Sn, Al, Ga, In) will undergo structural and magnetic characterization at pressures up to 10 GPa and temperatures down to a few Kelvins. The application of high pressure can enable transition from spin-glass states to magnetically ordered states as well as probe the electronic states and nature of magnetic interactions. Neutron scattering techniques will be used to investigate the nuclear structure, spin interactions and the arrangement of magnetic spins in a quasiperiodic lattice. X-rays (XRD technique) and optical photons (Raman spectroscopy) will also be used to elucidate the structure-properties relationships in QCs and ACs. The aim of this research is to contribute to the understanding of the effects of quasiperiodicity on the physical properties of materials and answer the fundamental question whether Tsai-type QCs containing rare earth elements can possess unique magnetic structures and properties.