Abstract
In this paper a quantitative theoretical formulation of the critical behavior of soft mode frequencies as a function of an applied magnetic field in two-dimensional Permalloy square antidot lattices in the nanometric range is given according to micromagnetic simulations and simple analytical calculations. The degree of softening of the two lowest-frequency modes, namely the edge mode and the fundamental mode, corresponding to the field interval around the critical magnetic field, can be expressed via numerical exponents. For the antidot lattices studied we have found that: a) the ratio between the critical magnetic field and the in-plane geometric aspect ratio and (b) the ratio between the numerical exponents of the frequency power laws of the fundamental mode and of the edge mode do not depend on the geometry. The above definitions could be extended to other types of in-plane magnetized periodic magnetic systems exhibiting soft-mode dynamics and a fourfold anisotropy.
Highlights
Since the pioneering works of the 60s and 70s on the static scaling laws[1,2] and on their generalization to dynamical properties of critical phenomena,[3,4,5] the critical behavior of dynamic excitations in physical systems has been widely investigated
We propose a quantitative study of the critical behavior as a function of the external magnetic field of the lowest-frequency modes, the so called soft modes, namely in order of increasing frequency the edge mode (EM) and the resonant mode of the system, the fundamental (F) mode, in 2D square antidot lattices (ADLs) having periodicity and holes size in the nanometric range.[16]
In this work the critical phenomena linked to the dynamics of soft modes studied as a function of an external magnetic field in 2D Py ADLs have been investigated from a quantitative point of view
Summary
Since the pioneering works of the 60s and 70s on the static scaling laws[1,2] and on their generalization to dynamical properties of critical phenomena,[3,4,5] the critical behavior of dynamic excitations in physical systems has been widely investigated. In these last years great attention has been devoted to the study of the static and dynamical properties of one-dimensional, two-dimensional (2D) and three-dimensional periodic magnetic systems, because of their challenging features.[10,11,12,13,14] In recent years, a series of works have focused the attention on the study of soft modes associated to critical phase transitions, for instance, in magnetic media exhibiting topological defects and in 2D antidot lattices (ADLs).[15,16].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
