Artificial spin ice(ASI) structures have significant technological potential as reconfigurable metamaterials and magnetic storage media.We investigate the field/frequency-dependent magnetic dynamics of a kagome ASI ma...Artificial spin ice(ASI) structures have significant technological potential as reconfigurable metamaterials and magnetic storage media.We investigate the field/frequency-dependent magnetic dynamics of a kagome ASI made of 25-nm-thick permalloy nanomagnet elements,combining magnetoresistance(MR) and microscale ferromagnetic resonance(FMR) techniques.Our FMR spectra show a broadband absorption spectrum from 0.2 GHz to 3 GHz at H below 0.3 kOe,where the magnetic configuration of the kagome ASI is in the multidomain state,because the external magnetic field is below the obtained coercive field Hc~0.3 kOe,based on both the low-field range MR loops and simulations,suggesting that the low-field magnetization dynamics of kagome ASI is dominated by a multimode resonance regime.However,the FMR spectra exhibit five distinctive resonance modes at the highfield quasi-uniform magnetization state.Furthermore,our micromagnetic simulations provide additional spatial resolution of these resonance modes,identifying the presence of two high-frequency primary modes,localized in the horizontal and vertical bars of the ASI,respectively;three other low-frequency modes are mutually exclusive and separately pinned at the corners of the kagome ASI by an edge-induced dipolar field.Our results suggest that an ASI structural design can be adopted as an efficient approach for the development of low-power filters and magnonic devices.展开更多
基金the State Grid Corporation of China via the Science and Technology Project:Research on Electromagnetic Measurement Technology Based on EIT and TMR(Grant No.JL71-18-007)。
文摘Artificial spin ice(ASI) structures have significant technological potential as reconfigurable metamaterials and magnetic storage media.We investigate the field/frequency-dependent magnetic dynamics of a kagome ASI made of 25-nm-thick permalloy nanomagnet elements,combining magnetoresistance(MR) and microscale ferromagnetic resonance(FMR) techniques.Our FMR spectra show a broadband absorption spectrum from 0.2 GHz to 3 GHz at H below 0.3 kOe,where the magnetic configuration of the kagome ASI is in the multidomain state,because the external magnetic field is below the obtained coercive field Hc~0.3 kOe,based on both the low-field range MR loops and simulations,suggesting that the low-field magnetization dynamics of kagome ASI is dominated by a multimode resonance regime.However,the FMR spectra exhibit five distinctive resonance modes at the highfield quasi-uniform magnetization state.Furthermore,our micromagnetic simulations provide additional spatial resolution of these resonance modes,identifying the presence of two high-frequency primary modes,localized in the horizontal and vertical bars of the ASI,respectively;three other low-frequency modes are mutually exclusive and separately pinned at the corners of the kagome ASI by an edge-induced dipolar field.Our results suggest that an ASI structural design can be adopted as an efficient approach for the development of low-power filters and magnonic devices.
