It seems like we're getting closer to the Star Trek future by leaps and bounds these days. We recently learned that a NASA scientist has set his sights on building a warp drive, and now news has come in that a team of physicists have built their own tractor beam in the lab. Now, it's nothing to get too excited over — they used an optical beam to pull a 30 micrometer silica sphere suspended in water — but the demonstration proved that a tractor beam can actually exist.
We've known about the power of Bessel beams for some time now, including their potential to act as a kind of tractor beam. This optical phenomenon was first discovered by Friedrich Bessel over a hundred years ago, and has since been applied by microbiologists as a kind of tweezer.