|The new material is suitable for solar cells, biosensors, and other systems working on quantum principles. |
Photo credit: Vladimir Petrov
Physicists at Ural Federal University and their colleagues from the Institute of Electrophysics, Ural Branch of the Russian Academy of Sciences, and the Institute of Ion Plasma and Laser Technologies, Academy of Sciences, have developed a technology for growing nonspherical nanoparticles that are synthesized by ion implantation. With the new technique, it is possible to grow nanoparticles of different shapes and thus obtain the necessary properties and control them. The technology is applicable to different metals, both noble metals such as gold, silver, platinum, and "ordinary", the scientists assure. A description of the technology and the results of the first experiments - copper implantation in ceramics - are presented in the Journal of Physics and Chemistry of Solids.
"By changing the shape of nanoparticles from spherical to non-spherical, we were able to increase the range of optical absorption. This, in turn, is the basis for further converting the absorbed energy into electricity and heat. As a result, we can get more functional sensors and increase their sensitivity range. If such nanoparticles are built into lasers, their power will increase. If we talk about sensors, their sensitivity will increase. As for sensors, their response time will change. This is all due to the peculiarity of plasmon resonance, which leads to the fact that around the nanoparticles there is an amplified electric field," explains study co-author Arseny Kiryakov, Associate Professor at the Department of Physical Techniques and Devices for Quality Control at UrFU.
Metal nanoparticles are used to solve a variety of problems: from biological (sensors for determining the composition of proteins, DNA analysis, etc.) to physical (creation of amplified lasers, photoluminescent sensors, etc.). For example, in contact with biobjects - DNA, viruses, antibodies - plasmonic nanostructures can increase the intensity of fluorescence signals by more than an order of magnitude, that is, they can significantly expand detection, identification and diagnosis. Changing the shape of nanoparticles will allow to control these properties, to improve them.
The first experiments with copper particles allowed scientists to create a metamaterial that has no analogues.
"The new material consists of non-spherical plasmonic nanoparticles in a matrix of optically transparent radiation-resistant ceramics. Due to the controlled morphology of the plasmonic nanoparticles, the new material provides improved spectral characteristics and energy conversion efficiency of the absorbed photons. We found that the unique physical properties of the obtained material are manifested by a special phenomenon - the effect of surface plasmon resonance. Materials with this effect can be used for new generation lasers, high-precision analytical devices, spacecraft navigation systems, quantum computers, etc., in other words, where light energy absorption and conversion should be used," says Anatoly Zatsepin, Professor of the Department of Physical Techniques and Devices for Quality Control at UrFU.
In addition, scientists from Uzbekistan, part of the research group, have proposed a universal matmodel describing this process. According to the physicists, the model is important for describing and understanding what happens to nanoparticles in different materials, and it is the first model that describes the growth of nonspherical nanoparticles. Previous models do not take into account the unusual shape of the particles.
Physicists plan to expand their understanding of the nature and laws of physical phenomena occurring in the material under external energy influences, which, in turn, will provide information about new possibilities for the functional application of this type of materials.
The new material is being researched under the Priority 2030 program at the Ural Federal University's Hybrid Technologies and Metamaterials - MetaLab research laboratory. The work is carried out within the framework of the project "Development of corpuscular-photon technologies for obtaining and modifying metamaterials for plasmonic, spintronics, and nanophotonic".
Metamaterial is an artificially created material that has no analogues in nature. Its properties are determined not so much by the properties of its constituent elements, as by its artificially created periodic structure. The structural elements are not atoms and crystal lattices, but special artificial elements, from which a new structure is assembled, resulting in a new material with different functional properties (optical, magnetic, electronic).
Source/Credit: Ural Federal University