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Simultaneous Synthesis of Single-walled Carbon Nanotubes and Graphene in a Magnetically-enhanced Arc Plasma
Published on: February 2, 2012
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Strong transient magnetic fields induced by THz-driven plasmons in graphene disks
Jeong Woo Han1, Pavlo Sai2, Dmytro B But2
1Universität Duisburg-Essen, Fakultät für Physik, 47057, Duisburg, Germany.
Nature Communications
|November 19, 2023
Summary
Engineered graphene disks generate strong, transient magnetic fields using plasmon resonances. This efficient method, observed via ultrafast Faraday rotation, offers new control over light-induced magnetism in metamaterials.
Area of Science:
- Condensed matter physics
- Plasmonics
- Metamaterials
Background:
- Circularly polarized light can induce effective magnetic fields in solids via inverse Faraday effects.
- Plasmonic resonances offer tunable control over light-matter interactions, unlike fixed material properties.
- Engineered metamaterials can enhance light-induced magnetic fields.
Purpose of the Study:
- To demonstrate efficient generation of light-induced transient magnetic fields using plasmonic circular currents in graphene disks.
- To explore the tunability of plasmon resonances for controlling magnetic field generation.
- To quantify the strength and dynamics of the induced magnetic field.
Main Methods:
- Fabrication of graphene disks to support plasmon resonances.
- Excitation with circularly polarized light at terahertz frequencies.
- Measurement of ultrafast Faraday rotation to detect induced magnetic fields.
- Comparison with simulations and reference measurements.
Main Results:
- Graphene disks exhibited plasmon resonance at 3.5 THz.
- A strong ultrafast Faraday rotation (~1°) was observed, indicating an induced magnetic field.
- The induced magnetic field was estimated to be ~0.7 T at a pump fluence of 440 nJ cm⁻².
- High efficiency in generating light-induced magnetic fields was achieved.
Conclusions:
- Plasmonic resonances in engineered graphene structures provide a highly efficient route to generate tunable, transient magnetic fields.
- This approach offers significant advantages over traditional methods limited by material properties.
- The findings open new avenues for controlling magnetism in metamaterials using light.
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