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Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
Magneto-optic fiber Sagnac modulator based on magnetic fluids
Peng Zu1, Chi Chiu Chan, Lew Wen Siang
1School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459.
Optics Letters
|April 19, 2011
Summary
This study introduces a novel magneto-optic modulator using magnetic fluid in a fiber optic Sagnac interferometer. The device effectively modulates light intensity with an external magnetic field, showing stable performance across temperatures.
Area of Science:
- Photonics and Optical Engineering
- Materials Science
- Magneto-optics
Background:
- Optical modulators are crucial components in fiber optic systems.
- Controlling light polarization and phase is essential for various applications.
- Magnetic fluids offer unique magneto-optic properties.
Purpose of the Study:
- To propose and demonstrate a novel magneto-optic modulator.
- To utilize the tunable birefringence and Faraday effect of magnetic fluids.
- To integrate these properties into a fiber optic Sagnac interferometer for light modulation.
Main Methods:
- A Sagnac interferometer was constructed using a single-mode optical fiber.
- A magnetic fluid film was inserted into the interferometer loop.
- An external magnetic field was applied to induce changes in the magnetic fluid.
- The output light intensity modulation was measured as a function of the magnetic field.
Main Results:
- The proposed device successfully modulated the output light intensity.
- The modulation was directly controlled by the applied external magnetic field.
- The modulator exhibited a high extinction ratio.
- Performance remained stable within a temperature range of 20 °C to 40 °C.
Conclusions:
- A novel and effective magneto-optic modulator based on magnetic fluid in a Sagnac interferometer has been demonstrated.
- The device offers a high extinction ratio and good temperature stability.
- This technology holds potential for integration into fiber optic sensing and communication systems.
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