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Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
Optically induced tunable magnetization dynamics in nanoscale co antidot lattices
Ruma Mandal1, Susmita Saha, Dheeraj Kumar
1Department of Condensed Matter Physics and Material Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700 098, India.
ACS Nano
|March 27, 2012
Summary
Researchers studied magnetic dynamics in cobalt antidot lattices. They found that changing the lattice spacing significantly alters the precessional mode bands and band gaps, enabling rich magnonic spectra.
Area of Science:
- Spintronics
- Condensed Matter Physics
- Materials Science
Background:
- Antidot lattices offer tunable magnetic properties.
- Understanding spin wave propagation in patterned magnetic materials is crucial for developing advanced spintronic devices.
Purpose of the Study:
- To investigate optically induced precessional dynamics in cobalt (Co) antidot lattices.
- To explore the influence of varying lattice constants on magnonic band structures.
Main Methods:
- Time-domain measurements of optically induced precessional dynamics.
- Fabrication of Co antidot lattices with fixed antidot diameter (100 nm) and varying lattice constants (S = 200–500 nm).
- Numerical calculations of mode profiles and magnonic spectra.
Main Results:
- Observed two bands of precessional modes with a band gap in the sparsest lattice.
- Noted a substantial increase in the band gap as lattice constant (S) decreased to 300 nm.
- Identified four distinct bands with significant band gaps at S = 200 nm.
- Numerical simulations revealed localized and extended modes propagating perpendicular to the bias magnetic field.
- Demonstrated composite antidot structures exhibiting rich magnonic spectra from 3 to 27 GHz.
Conclusions:
- Lattice constant is a critical parameter for controlling magnonic band gaps in Co antidot lattices.
- The observed rich magnonic spectra in engineered structures hold promise for magnonic device applications.
- Optically induced dynamics provide a powerful tool for probing and manipulating spin wave phenomena.
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