Light has an inherent power to move microscopic objects – a property previously used to develop the Nobel prize-winning research idea of ‘optical tweezers’, which use a highly focused laser beam to control and manoeuvre tiny particles with incredible precision.
Now, a research group at Chalmers University of Technology and the University of Gothenburg, both of Sweden, has shown how even an unfocused light can be used to manoeuvre microscopic particles in a controlled manner. Their research has been published in the journal Nature Nanotechnology.
The researchers manufactured vehicles at a scale of 10 micrometres wide and 1 micrometre thick (one thousandth of a millimetre). The vehicles consisted of a tiny particle, coated with a ‘metasurface’. Metasurfaces are ultra-thin arrangements of carefully designed and ordered nanoparticles, engineered to direct light in interesting and unusual ways. They offer fascinating possibilities for use in advanced components...