The idea of moving objects with light is not a new one. Solar sails, such as those used by Japan's IKAROS spacecraft, harness the sun's radiation for propulsion. But researchers at the Rochester Institute of Technology have shown that light can also generate the much more complex force known as lift – the same force that allows airplanes' wings to hoist them aloft as they move through the air.
Lift occurs when a push in one direction causes an object to move perpendicularly to that push. In the new lightfoil, light takes the place of the typical air or water to create that flow on a small scale. The team, led by Grover Swartzlander, fashioned micro-rods in the shape of an airplane wing (one side flat, one side rounded) and submerged them in water. Then they shot these lightfoils with 130 milliwatts of light, creating, for the first time optical lift. The rods moved up and to the side, as can be seen in the video below.
Compared with aerodynamic lift created by airfoils, this optical lift has an extremely steep angle – about 60 degrees. Light is refracted differently within the rod depending on its point of entry, and the bending of the beam causes lift.
While optical lift probably isn't going to be used to fly 747s anytime soon, it could prove useful in powering micromachines or transporting nanoparticles. Swartzlander says he also believes that optical lift could be used to steer solar-sail-powered craft like IKAROS, which currently can only move straight in the direction the sun pushes it, and requires external forces, like jets of gas, to change direction.
Interesting..I'm in my fourth year of studying to be an aero engineer so I wonder how this compares. Obviously not pressure differentials like aerodynamic lift. I didn't really understand what they article was saying about the bent light generating lift depending on it's point of entry, though I assume it's comparable to the angle of attack? And does the airfoil have to be transparent then so it's refracted?
I remember reading about this concept as science fiction in high school. It was also listed as one of the possible light speed devices.
I assume that when this technology gets used in vehicles, it will just be annother toy for the wealthy. I wonder if the public could ever get to own anything innovative for a low cost.
I see this device as being a tool used by socialist nations to contain the starving people within it's borders: sort of a "light barrier" so they can brag they don't need walls any more.
This really is groundbreaking. I wonder how long it will be until we reach speed of light travel or at least a speed where i wont take 3000 life times to reach the next solar system?