Light-Induced Pulling and Pushing by the Synergic Effect of Optical Force and Photophoretic Force
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Chinese scientists have harnessed the heat produced by light to move an object, opening the door for devices that use light to generate mechanical forces, according to a study published in Physical Review Letters.
Researchers from Zhejiang University used a beam of light to transport a tiny gold plate along a tapered optical fibre by utilizing heat generated by the light as it struck the plate’s surface.
By illuminating one side of the plate, the surrounding air warmed, producing hotter, faster-moving molecules that exerted a greater force on the illuminated side than the cooler side, causing the plate to move along the fibre. As the plate neared the end of the fibre, the cooler side of the plate warmed, reversing its direction.
The technique could be used in optical control and sensing applications, and for transporting objects in miniature lab-on-a-chip devices.
- Phys. Rev. Lett. 118, 043601 (2017). doi: 10.1103/physrevlett.118.043601
|Zhejiang University (ZJU), China||1.00|