Study of different physical properties of some quasi-one-dimensional spin chain compounds
by Dr. Moumita Nandi (Saha Institute of Nuclear Physics, Kolakta)
Friday, October 6, 2017 from to (Asia/Kolkata)
Low-dimensional magnetic systems like spin-chain compounds have attracted immense interest of scientific community due to their complex magnetic properties and spin excitations. Spin chain compound CoNb2O6 is an ideal system for exploring transverse field Ising chain model and complex magnetic ground state properties. We have investigated structural, magnetic and thermodynamic properties of quasi-one-dimensional Ising spin chain compounds -CoV2O6, -CoV2O6 and CoNb2O6. All three compounds exhibit field-induced metamagnetic transitions with 1/3 magnetization plateau. These field induced magnetic transitions have been reflected in measurements of other physical parameters like heat capacity, thermal expansion, dielectric constant etc. Below a certain critical temperature 6 K, we have observed additional field-induced magnetization plateaus in -CoV2O6 which may indicate appearance of some complex magnetic phases in low temperature. A new phase diagram has been constructed for -CoV2O6 from low temperature magnetization measurements and magnetic entropy calculations. Our thermal expansion and magnetostriction measurements reveal presence of strong spin-lattice coupling in -CoV2O6 and CoNb2O6. We also have found magneto-dielectric coupling in CoNb2O6. Additionally, our calculated magnetocaloric parameters suggest that all three spin-chain compounds can also be suitable for magnetic refrigeration.