Physicists at New York University have demonstrated a micro-tractor beam capable of pushing and pulling molecules.

The system by David B. Ruffner and David G. Grier consists of a set of superimposed Bessel beams—beams which do not spread and are capable of self healing after partial obstruction—which is able to push and pull tiny objects along its length.

According to the project's abstract: "These optical conveyors have periodic intensity variations along their axes that act as highly effective optical traps for micrometer-scale objects."

The duo's tractor beam is closer to the traditional science fiction concept of light-based transportation as it emits from a single source rather than relying on light from opposing points of origin to move the matter up and downstream. It is also reportedly more stable than other options:

"Optical conveyors thus have the potential to out-perform optical tweezers, which cannot always achieve stable axial trapping," state Ruffner and Grier.

While the current offering is only suited for moving microscopic particles, the team are already making suggestions to improve the mini tractor beam including improving speed of transportation by using a brighter conveyor and using higher order conveyors to transport oddly shaped objects.