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Updated: Mar 14, 2026
08:01
Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
7.8K
Optical bistability in core-shell magnetoplasmonic nanoparticles with magnetocontrollability.
Optics Express
|September 24, 2016
Summary
We demonstrate tunable optical bistability in nanospheres using magnetic fields. This magneto-optical effect in nonlinear nanostructures offers potential for advanced optical nanoswitches and nanosensors.
Area of Science:
- Nanophotonics
- Nonlinear Optics
- Magneto-Optical Materials
Background:
- Optical bistability is crucial for all-optical switching.
- Tuning bistability typically requires complex experimental setups.
- Magneto-optical materials offer field-tunable optical properties.
Purpose of the Study:
- To propose and numerically investigate a mechanism for actively tuning optical bistability.
- To explore the use of nonlinear coated nanospheres with magneto-optical shells and nonlinear metallic cores.
- To demonstrate magneto-controllable optical bistability.
Main Methods:
- Numerical simulations of nanosphere optical response.
- Analysis of surface plasmon resonance effects.
- Investigation of varying magnetic field strengths and polarization states.
Main Results:
- Optical bistability observed near surface plasmon resonance wavelengths.
- Bistability is tunable via external magnetic fields.
- Existence of bistability depends on metallic core volume fraction (η > ηc).
- Bistable behavior is sensitive to incident polarization and magnetic field strength.
Conclusions:
- Nanostructures with magneto-optical shells and nonlinear metallic cores exhibit tunable optical bistability.
- External magnetic fields can modify threshold fields and critical volume fractions.
- These findings pave the way for novel nonlinear optical nanodevices like nanoswitches and nanosensors.
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