The light-driven plasmonic nanorobot is a sub-micrometer research robot developed at Julius-Maximilians-Universität Würzburg (JMU) in the Nano-Optics and Biophotonics Group led by Prof. Bert Hecht. The work was published in Nature Communications (27 March 2026) as “A nanoscale robotic cleaner”, authored by Jin Qin, Carsten Büchner, Xiaofei Wu and Bert Hecht.
The robot is actuated by photon recoil. A plasmonic directional antenna simultaneously provides the propulsion force and orientation control, without beam steering or tight focusing, mitigating system complexity and photodamage. The direction of motion is intrinsically locked perpendicular to the linear polarization axis, while circularly polarized light pulses lift the twofold orientational degeneracy through spin-momentum transfer. The nanorobot reaches propulsion speeds up to 50 µm/s.
Using opto-thermophoretic forces, the nanorobot captures, transports, reversibly assembles and releases bacteria. By sequencing linear and circular polarization states it executes complex, high-precision trajectories to systematically sweep defined regions, functioning as a light-driven robotic cleaner. The work expands the capabilities of nanorobots for biological manipulation and high-speed, localized sensing.
Dimensions, weight and structural proportions
