Scaling of nonlinear susceptibilities in artificial permalloy honeycomb lattice

Abstract

Two-dimensional artificial magnetic honeycomb lattice is predicted to manifest thermodynamic phase transition to the spin solid order ground state at low temperature. Nonlinear susceptibilities are very sensitive to thermodynamic phase transition. We have performed the analysis of nonlinear susceptibility to explore the thermodynamic nature of spin solid phase transition in artificial honeycomb lattice of ultra-small connected permalloy (Ni${}_{0.81}$Fe${}_{0.19}$) elements, typical length of $\simeq$ 12 nm. The nonlinear susceptibility, ${\chi }_{n1}$, is found to exhibit an unusual cross-over character in both temperature and magnetic field. The higher order susceptibility ${\chi }_3$ changes from positive to negative as the system traverses through the spin solid phase transition at $T_s$ = 29 K. Additionally, the static critical exponents, used to test the scaling of ${\chi }_{n1}$, do not follow the conventional scaling relation. We conclude that the transition to the ground state is not truly thermodynamic, thus raises doubt about the validity of predicted zero entropy state in the spin solid phase.

arXiv comment5 pages, 4 figures

References in corpus (11)

• Colloquium: Artificial spin ice: Designing and imaging magnetic frustration
• Direct observation of the ice rule in artificial kagome spin ice
• Static Critical Behavior of the Spin-Freezing Transition in the Geometrically Frustrated Pyrochlore Antiferromagnet Y2Mo2O7
• Magnetic multipole analysis of kagome and artificial ice dipolar arrays
• Two-stage ordering of spins in a dipolar spin ice on the kagome lattice
• Dynamics of magnetic charges in artificial spin ice
• Diversity enabling equilibration: disorder and the ground state in artificial spin ice
• Magnetic diffuse scattering in artificial kagome spin ice
• Temperature Dependent Magnetism in Artificial Honeycomb Lattice of Connected Elements
• Spin Solid versus Magnetic Charge Ordered State in Artificial Honeycomb Lattice of Connected Elements
• New Description of Evolution of Magnetic Phases in Artificial Honeycomb Lattice

Cited by in corpus (1)

• Various facets of magnetic charge correlation: Micromagnetic and distorted waveBorn approximation simulations study