Scaling of nonlinear susceptibilities in an artificial permalloy honeycomb lattice
Abstract
Two-dimensional artificial magnetic honeycomb lattice is predicted to manifest several magnetic phase transitions as a function of reducing temperature. We have performed the analysis of nonlinear susceptibility to explore the equilibrium nature of phase transition in artificial honeycomb lattice of ultrasmall connected permalloy (Ni0.81Fe0.19 ) elements, typical length of ≃12 nm. The nonlinear susceptibility χn 1 is found to exhibit an unusual crossover character in both temperature and magnetic field. The higher order susceptibility χ3 changes from positive to negative as the system traverses through the spin solid phase transition at Ts=29 K. Additionally, the static critical exponents, used to test the scaling of χn 1, do not follow the conventional scaling relation. We conclude that the magnetic phase transition, especially to the low temperature spin solid order, is not conventional in nature at this length scale.
- Publication:
-
Physical Review B
- Pub Date:
- June 2018
- DOI:
- 10.1103/PhysRevB.97.214420
- arXiv:
- arXiv:1802.06325
- Bibcode:
- 2018PhRvB..97u4420D
- Keywords:
-
- Condensed Matter - Mesoscale and Nanoscale Physics
- E-Print:
- 5 pages, 4 figures