They hope that, in future, electron microscopes can not only be used to move electrons around, but to assemble nano structures as well.
The researchers, NIST metallurgist Vladimir Oleshko and UVA materials scientist James Howe, made the discovery as they were studying melting and crystallization. "We can generate this sphere inside the liquid shell easily; you can tell from the image that it's still crystalline," Oleshko said. "But we saw that when we move or tilt the beam—or move the microscope stage under the beam—the solid particle follows it, like it was glued to the beam."
The researchers said that such electron tweezers could have a great impact in material science as it would allow scientists to precisely position materials on an atomic level: "Of course, this is challenging because it requires a vacuum," Oleshko said. "But electron probes can be very fine, three orders of magnitude smaller than photon beams—close to the size of single atoms."