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Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
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Directional Bloch surface wave coupling enabled by magnetic spin-momentum locking of light
Kaiwen Luo1, Zhijing Huang1,2, Xianpeng Lv1
1Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Department of Optoelectronic Engineering, Jinan University Guangzhou 510632 China thuihuilu@jnu.edu.cn.
Nanoscale Advances
|March 17, 2023
Summary
We demonstrate directional control of optical surface waves using circularly polarized light. This magnetic spin-locking phenomenon enables precise nano-routing of Bloch surface waves (BSWs) for advanced photonic devices.
Area of Science:
- Photonics and Optics
- Condensed Matter Physics
- Nanotechnology
Background:
- Optical surface waves, specifically Bloch surface waves (BSWs), are crucial for integrated photonic devices.
- Controlling the directionality of light propagation at the nanoscale is a key challenge in photonics.
Purpose of the Study:
- To investigate the magnetic spin-locking of optical surface waves.
- To achieve directional coupling and nano-routing of transverse electric (TE) polarized BSWs.
- To explore the role of optical magnetic fields in controlling light propagation.
Main Methods:
- Utilizing an angular spectrum approach and numerical simulations.
- Employing a high-index nanoparticle as a magnetic dipole and nano-coupler on a 1D photonic crystal.
- Using circularly polarized light to mimic a spinning magnetic dipole.
Main Results:
- Demonstrated directional coupling of light into BSWs.
- Showed that light helicity controls the directionality of emerging BSWs.
- Achieved directional nano-routing of BSWs using silicon strip waveguides.
Conclusions:
- The directional coupling of BSWs is solely mediated by the optical magnetic field.
- This work enables directional switching and polarization sorting in ultra-compact architectures.
- Offers new avenues for investigating the magnetic polarization properties of light.
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