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Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
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Spin photonic forces in non-reciprocal waveguides
Optics Express
|September 7, 2018
Summary
Researchers explored optical forces in non-reciprocal structures, revealing that particle motion induces forces. This discovery links photon spin to controlling nanoscale optical forces on-chip.
Area of Science:
- Photonics
- Nanotechnology
- Optical physics
Background:
- Optical forces are crucial for manipulating nano/micro-particles.
- Understanding these forces is well-established in reciprocal structures with time-reversal symmetry.
Purpose of the Study:
- Investigate optical forces in non-reciprocal structures.
- Analyze forces in systems with non-degenerate counter-propagating modes.
- Explore non-reciprocity induced by translational motion.
Main Methods:
- Considered a moving slab-waveguide to induce non-reciprocity.
- Analyzed non-degenerate counter-propagating modes.
- Investigated near-field photonic spin and spin-momentum locking of evanescent waves.
Main Results:
- Non-degenerate counter-propagating modes in a moving slab-waveguide result in non-zero lateral and longitudinal forces on nanoparticles.
- Anomalous forces are fundamentally linked to near-field photonic spin.
- Directionality of forces is explained by spin-momentum locking of evanescent waves.
Conclusions:
- The interplay of photon spin and non-reciprocity offers novel methods for controlling nanoscale optical forces.
- This research opens new avenues for on-chip optical manipulation.
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