Optical tweezers enable the manipulation of micro-and nano dielectric particles through entrapment using a tightly
focused laser. Generally, optical trapping of sub-micron size particles requires high intensity light in the order of MW/cm2.
Here, we demonstrate a technique of stable optical trapping of submicron polymeric beads on nanostructured rare metal
surfaces (RMS) without the use of lasers. Fluorescent polymer beads with diameter d = 20 – 500 nm were successfully
trapped on the nanostructured RMS by low-intensity focused illumination of incoherent light at =370 m from a Hg lamp.
Light intensity was 5.5 W/cm2, corresponding to a reduced light intensity of 6 orders of magnitude. Upon switching off
illumination, trapped particles were released from the illuminated area, indicating that the trapping was optically driven
and reversible. The nanostructures were demonstrated to play a key role.
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