Precise radiation sources are expected to cause breakthroughs in medical imaging and other fields

Researchers at the Technion have developed precise radiation sources that may replace expensive and cumbersome particle accelerators that are currently used to create radiation such as X-rays. These new sources produce controlled radiation with a narrow and precise spectrum and high resolution, and this with a relatively low energy investment

Researchers at the Technion have developed precise radiation sources that may replace expensive and cumbersome particle accelerators that are currently used to create radiation such as X-ray radiation. These new sources produce controlled radiation with a narrow and precise spectrum and high resolution, and this with a relatively low energy investment. Therefore, they are expected to lead to applied breakthroughs in diverse contexts - spectral analysis of chemical and biological substances, medical imaging, X-ray equipment in security checks and other uses that require reliable sources of precise radiation.

the study published yesterday in the journal Nature photonics It was led by Dr. Ado Kaminer and Master's Degree Michael Shantzis. Dr. Kaminer is Head of the Laboratory for Quantum Dynamics of Electron Beams named after Robert and Ruth Magid, faculty member in the Faculty of Electrical Engineering named after Viterbi and the solid state institute and friend at the Russell Berry Nanotechnology Institute (RBNI) and at the Quantum Center by Helen Diller.

The current article presents a first experimental observation that is proof of the feasibility of a theoretical model developed in the last decade in a series of seminal articles. The first article on the subject, which appeared in the same journal (Nature photonics), written by Dr. Kaminer at MIT with his postdoctoral supervisors, Prof. Marin Sulejcic and Prof. John Joanopoulos. In the same article Kaminer and his colleagues presented A theoretical concept for using two-dimensional materials to create X-rays. That article, according to Dr. Kaminer, marked the "beginning of a journey to radiation sources based on the unique physics of two-dimensional materials and various combinations between them - heterostructures." We have continued to develop the theoretical breakthrough from that article in a series of theoretical articles since then, and now we are excited to announce The first experimental observation In creating X-ray radiation in such devices, while precisely controlling the parameters of the radiation."

Two-dimensional materials are unique artificial structures that burst into consciousness around 2004 with the development of graphene by the physicists Andre Geim and Konstantin Novoslov - later winners of the Nobel Prize in Physics for 2010. Graphene is an artificial surface of carbon atoms, i.e. a structure with a thickness of a single atom, which does not exist in nature. The first graphene structures were created by the two novelists by peeling off thin layers of material from graphite, the "writing material" in the pencil, using adhesive paper. The two, and researchers who followed them, discovered that graphene has unique and surprising properties that are different from the properties of XNUMXD graphite: strength (graphene is tens of times stronger than a steel sheet of similar thickness), almost complete transparency, electrical conductivity and the ability to conduct light that enables the emission of radiation - a central aspect of the current article. These unique properties make graphene, and other XNUMXD materials, promising players in the next generations of chemical and biological sensors, solar cells, semiconductors, screens, and more.

The invention of graphene opened a new field of research focusing on various two-dimensional materials, including van der Waals materials (vdW materials) which were the focus of Dr. Kaminer's current research. These materials are named after Johannes Diedrik van der Waals, who won the Nobel Prize in Physics exactly one hundred years earlier, in 1910.

Dr. Kaminer and Michael Shentzis created different vdW materials and sent electron beams through them at specific angles, which led to a controlled and precise emission of X-ray radiation. This is how the first experimental observation of X-ray radiation emitted from vdW materials was achieved. Furthermore, the researchers demonstrated precise tuning (tunability) of the radiation spectrum with an unprecedented resolution, and this with a minimal investment of energy and while taking advantage of the flexibility in designing families of vdW materials.

In conclusion, the new article by Dr. Kaminer's research group contains experimental results, a new theory and proof of the feasibility of an innovative application of two-dimensional materials as systems that produce controlled and precise radiation. According to Dr. Kaminer, "the experiment we conducted, and the theory we developed to explain it, make a significant contribution to the physical research of light-matter interaction and pave the way for many and varied applications in X-ray imaging, in X-ray spectroscopy used to characterize materials, and more, and in the future will make it possible to create quantum light sources in the X-ray field .”

In the current study, conducted as mentioned in collaboration between various units at the Technion, researchers from the Shulich Faculty of Chemistry, the Faculty of Materials Science and Engineering and the following institutions participated: The Barcelona Institute of Science and Technology, ICREA Institute in Barcelona, ​​Arizona State University, Technical University of Denmark and Nanyang Technological University in Singapore.

All feasibility proof experiments were conducted in the electron microscopes at the MICA Microscopy Center in the Faculty of Materials Science and Engineering.

The research was also supported by the European Union (ERC grant and H2020 grants), the Israel National Science Foundation (ISF) and the Azrieli Foundation.