According to the latest issue of The Science, the Institute of physics of Graz University of technology in Austria, has successfully performed three-dimensional imaging of nano surface phonons for the first time, with the laboratory of solid state physics of the University of South Paris in France, which is expected to promote the development of new and more effective Nanotechnology.
Whether it is microscopy, data storage or sensor technology, it depends on the electromagnetic field structure of the material surface. In nanosystems, the time distortion of the surface phonon atomic lattice plays a decisive role in the physics and thermodynamic properties. If the surface phonons can be manipulated specially, it is possible to achieve better heat transfer between two components with nano surface.
Surface phonons can be used in detectors, sensors or efficient passive cooling systems. In addition, the surface phonons concentrate the electromagnetic energy in the far-infrared range, which paves the way for making super-resolution lens and improving vibration spectrum. Despite its great potential, scientists still have little exploration in this field. In order to develop new nanotechnology, it is necessary to visualize the surface phonons at the nanoscale.
“Visualizing these local fields is the starting point for a deeper understanding of basic principles and better design of nanostructures.” Gerald kosleitner, director of the Institute of electron microscopy and nanoanalysis at Graz University of technology, said, “it was only a few years ago that we developed an electron microscope that can record the lower energy of phonons. So far, they can only be measured in a two-dimensional plane. “
In the new study, they activated these lattice vibrations with an electron beam, measuring them with a special spectral method, and then reconstructed them with tomography. As a result, the infrared light field generated by the surface phonons of MgO nanocube was visualized in three-dimensional space for the first time. This makes it possible for researchers to process images of the strong interaction between some phonons and the environment. One of the researchers, Ulrich hornster of the Institute of physics at the University of technology in Graz, compared the X-ray image with the computed tomography process. “3D reconstruction of objects can be created by many synthetic 2D projections.” “Just like on a violin or guitar, the vibrations on the surface of a nanocube are broken down into a series of resonances,” he said. By choosing these models, we can get the best consistency with the experimental data. ”
