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Tiny, hollow wires can produce doughnut-shaped laser light that could be used to levitate small objects or transmit information.
Conventional lasers typically make beams that appear as a single, small point of light when they hit a surface. But for some novel communication technologies that use light to transfer information, it can be better to use lasers that produce hollow beams like a drinking straw, which appear as a ring of light when they hit a surface.
Such hollow laser…