Superparamagnetic nanoparticles vs. ferromagnetic nanowires: a comparative simulation study for high-frequency inductor applications
Journal
Journal of Magnetism and Magnetic Materials
Journal Volume
629
Start Page
173221
ISSN
0304-8853
Date Issued
2025-10-01
Author(s)
Peng, Chih-Chen
Wu, Cheng-Jun
Lai, Sheng-Chih
Hu, Chen-Yu
Song, Mingyuan
Bao, Xinyu
Lin, Yu-Ming
Abstract
Magnetic core materials play a crucial role in advancing the performance of high-frequency on-chip inductors. This study investigates two promising candidates, superparamagnetic nanoparticles (SPM NPs) and ferromagnetic thin-film nanowires (FM NWs), through comprehensive simulations to evaluate their potential for high-frequency applications. For the SPM NP system, we demonstrate that increasing saturation magnetization (Ms) and damping constant significantly improves performance, while inter-particle interactions influence material characteristics depending on packing geometry. For the FM NW system, a bi-anisotropy model based on shape anisotropy shows that Ms is the primary factor limiting frequency performance. Under the consideration of dipolar field effect, the system achieves an effective permeability (μeff) of 1.62 and a ferromagnetic resonance frequency (fr) of 17.1 GHz with an Ms of 1000 emu/cc. In conclusion, analytical formulas are provided to account for volume fraction, enabling performance prediction and optimization for both systems. While SPM NPs can achieve higher frequency limit, they are limited in μeff. In contrast, FM NWs offer a better balance between μeff and fr. This simulation-based study offers valuable insights into the trade-offs and design considerations for magnetic core materials in next-generation high-frequency inductors.
Subjects
Blocking resonance
Ferromagnetic resonance
High frequency
Magnetic nanoparticle
Magnetic nanowire
Permeability
Publisher
Elsevier BV
Type
journal article