Dr. Tomer Lewi – Trying to Beat Nature

Dr. Tomer Lewi, an expert in Nano Photonics and Flat Optics at Bar-Ilan’s University Alexander Kofkin Faculty of Engineering, shares his experience with metamaterials and their applications, which may enable the replacement of classic optical elements with flat ones.

The interaction between light and matter is the focus of research for Dr. Tomer Lewi, of Bar-Ilan’s Faculty of Engineering. “I am interested in the interaction between light and metamaterials or quantum materials,” explains Lewi. “Why? Two reasons. Firstly, because it’s interesting on the physical level.  New phenomena arising suddenly, exciting new functions. Secondly, these materials are used to develop a new type of technology called Flat Optics, aiming to replace all the classic optical elements, such as lenses, mirrors, beam splitters and such, with flat elements – nanostructures designed for specific functions.”

But how does Flat Optics work? “Metasurfaces are two-dimensional arrays of tiny optical antennas, the size of each is smaller than the wavelength of the incident light. When light waves hit these structures, a very strong interaction can occur,” explains Lewi. “Careful design of these nanostructures, allows light to resonantly excite optical oscillations in each of the tiny antenna elements, so that we can control both the light’s amplitude and phase. By varying the size of each nano-antenna in the array, or by locally modulating their optical properties, we are able to control light’s phase and amplitude, and produce nearly any optical function we desire in this component. Eventually this technology, which allows us to bend, reshape and manipulate light in ways which were not possible before, will replace the traditional bulky optical elements in our cameras, phones, microscopes etc. with nanostructures made of silicon or other semiconductors. Our objective is to miniaturize all optical components exiting today, improve their performance, and enable other features that are currently impossible.”

Lewi, a married father of two, joined BIU in July 2018 as a senior lecturer at the Electro Optics Track at the Faculty of Engineering, and as a researcher at the Bar-Ilan Institute for Nanotechnology and Advanced Materials. He completed a BSc in Electrical Engineering at Tel Aviv University and at HIT, and his MSc and PhD in Physics at Tel Aviv University, where he studied infrared photonics.  He completed a postdoctoral fellowship at the University of California Santa Barbara (UCSB) and the California Nanosystems Institute (CNSI), where for nearly 4 years he studied nano-antennas and optical metasurfaces. “Metamaterial research is essentially an attempt to beat nature. Engineering ‘artificial materials’ exhibiting properties that cannot be found in natural materials” says Lewi. “The metasurfaces we create enable us to control a range of quantum physics phenomena such as, photon entanglement and spontaneous emission from quantum emitters and nano-lasers, which will in return, enable us to enhance their efficacy in the future.”

Lewi is now preparing a course about fundamentals of semiconductor devices, and establishing his lab. He is currently recruiting new staff- a lab manager, grad students, PhD candidates and post docs. “I’m looking for talented, highly motivated people to join me and study this fascinating area of research, which is interesting both on the fundamental physics level and also from its technological potential,” says Lewi. “I hope that our research will enable us to better understand the interaction between light and quantum materials and nanostructures, and through that – discover interesting new phenomena. I also expect our future work to help revolutionize the field of optics through the development and implementation of flat optics. In less than a decade I hope to lead a large motivated research group of about 8-10 excellent scientists, teach a wider range of classes and establish myself in the university. I am delighted to be a part of the Bar-Ilan Faculty of Engineering, with its vibrant, innovative and friendly atmosphere, and mostly its incredible people. At the end of the day, this is the key to success and not just in science”.