Reaching the nearest star system, Alpha Centauri, would take hundreds of thousands of years using current rocket propulsion technology. Researchers in the J. Mike Walker ’66 Department of Mechanical Engineering at Texas A&M University have demonstrated a new approach to light-driven motion, showing that lasers can be used to lift and steer objects in multiple directions without physical contact. This breakthrough may one day enable travel to Alpha Centauri within roughly 20 years.
Dr. Shoufeng Lan , assistant professor and director of the Lab for Advanced Nanophotonics, and his team published the work, “ Optical propulsion and levitation of metajets ,” in Newton. The study introduces micron-scale devices, termed “metajets,” that generate controlled motion when illuminated by laser light.
These metajets are composed of metasurfaces — ultrathin materials engineered with tiny patterns that enable scientists to control how light behaves, much like shaping a lens, but on a much smaller and more precise scale. By carefully designing these structures, the research team controlled how light transfers momentum to an object, enabling it to move.
Lan compares the effect to ping pong balls bouncing off a surface: when light reflects, it transfers momentum, creating a small but measurable force that can push an object.
The metajets demonstrate full three-dimensional maneuverability, a capability not previously realized in optical propulsion systems. To the team’s knowledge, this is the first demonstration of 3D maneuvering using this type of approach.
While related work has emerged from research groups in Europe, Lan said the Texas A&M team advances the field of developing a broader framework based on fundamental physics principles that describe how light generates force. In the United States, similar efforts include work at the California Institute of Technology focused on propulsion stability as well as the Rochester Institute of Technology utilizing diffractive grating platforms.
Unlike conventional methods that control objects by shaping the light itself, this approach builds control directly into the material. This allows for more flexible force generation, suggesting that the concept could scale more easily. The force depends on the power of the light rather than the size of the device, meaning the same principles could apply beyond microscopic systems.
Although current devices are only tens of microns in size, smaller than the width of human hair, the underlying physics suggests the approach could extend to much larger systems if sufficient optical power is available.
Fabricating the metasurfaces required nanoscale precision, with each feature carefully designed in shape, orientation and placement.
The devices were produced at the Texas A&M AggieFab Nanofabrication Facility, supported by the Texas A&M Engineering Experiment Station (TEES) and the university. To test the devices, researchers conducted experiments in a fluid environment to help offset gravity and better observe the motion.
The project was carried out by doctoral students in Lan’s group, who led both the design and experimental validation. Lan noted that the research has also influenced curriculum development, with the underlying physics of light-induced forces incorporated into graduate coursework, generating increased interest in undergraduate research opportunities.
The team is now pursuing external funding to extend testing into microgravity environments, where light-driven propulsion could be studied without the constraints of gravity.
The findings contribute to a growing area of research focused on controlling objects with light and understanding how light interacts with physical systems. They suggest a future where light could be used to move and control objects ranging from microscopic devices to spacecraft, without the need for physical contact or fuel.
By Maddi Busby , Texas A&M University College of Engineering
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