Meet your Scientist
Menu index

Interview with
Shai Tsesses

What is your specific area of research? How would you explain it to young children?
I am exploring many aspects of how light affects matter at the nano-scale, mostly through controlling plasmonic fields – surface waves of light. One of these aspects is how we can use plasmonic fields to shape free electrons, which is my part in this project. To put things in a more simplified perspective, I’m like a kid trying to put his hand in water, and wiggle it hard and fast enough so that the water would make an interesting shape, except instead of using my hand, I’m using light; and instead of shaping water, I’m shaping electrons (which are kind of like water). 

Why did you choose your research field? Were you inspired by someone?
I wasn’t really inspired by a person, but I just found that I really (really) like wave phenomena. I found that I understand every physical process through wave phenomena much better than I did through the regular way of explaining them. As an undergraduate student I tried looking for a job as research assistant in a lab that dealt with any kind of wave phenomenon in my department, and my current advisor is actually the only one that answered my email! The rest is history. 

How does your life as a top scientist compare with your expectations of it when you enrolled in Physics?
I don’t really think of myself as a “top” scientist. I’m just me, trying to lead my own life. Being a scientist is my job, but what’s fun about it is that I can ask myself whatever questions I want and try to find answers. I think I’d be the same no matter what profession I’d take up, but being a scientist sure gives you much more freedom to explore! 

What traits might a child possess that may indicate an interest or aptitude for your research field?
Curiosity and imagination. I wasn’t born a physicist, but I always liked inventing stories, exploring histories and myths or trying to answer interesting puzzles. I think that anyone with the will to explore and imagine new things can be successful in our research field, they just have to agree to learn math as well!  

What are you currently working on and what is your long-term research goal?
I’m currently trying to develop the technology to shape electron beams using surface waves of light, such that by controlling the shape or amplitude of the surface wave, I’d be able to control the shape of the electron beam. This mechanism is actually very similar to the Acousto-Optical Modulator in optics, but here the light plays the part of the acoustic waves. My long-term goal is for this technology to mature into an actual device, allowing us arbitrary control over electron beam shapes. 

Do you have an analogy to help our readers to understand your work?
Sure. Think about the laser show in the last music festival you went to (I’m assuming it had a laser show), or the advanced surround-sound system that was used in the last movie you went to (do they still have those?). The laser show was able to produce various shapes in the sky by controlling the illumination pattern, and the surround-sound system changed its sound projection according to the position of a car moving on the screen. Oddly as it may sound, we are now trying to do the same thing, but for streams of charged particles – electrons.

What is it that excites you about your work?
I like that it’s at the interface between fundamental and applied physics. Obviously we’re trying to create a technology that will be used for many different and important things, but at the same time – not all the questions are answered. We don’t know what are the limits or how far we can push it yet, so it’s always exciting to try and explore new frontiers. 

Why is your research important?
It could solve a whole bunch of problems and open an unforeseeable amount of new applications, but I’m most excited about trying to use it to solve the global chip shortage. The main bottleneck in chip production is the need to replace lithography masks and realign the manufacturing systems every time you wish to produce a different chip. What if you didn’t have to do that? What if you could just use electrons – without the need for scanning, mind you – to produce chips and never replace the mask, since it’ll be programmable? I’m very much looking forward to seeing if we can help solve this very important problem. 

Is there a story/anecdote about your work that you would like to share with us?
I think the way I found myself in my current project is pretty random. I was invited to a conference about controlling electron beams (presenting something completely unrelated), and I was exposed to this huge problem of trying to actively control electron beams. It’s not so much that it was highlighted, but the state-of-the-art at the time left such a bad impression on me, that I thought “there has to be a better way to do it! This is a really important problem!”. So I dedicated a lot of time and effort in order to try and realize it with the tools at my disposal.

Would you like to mention one or more of your most important scientific findings?
After several years of research, I am happy to say that we now have the capability to actively control electron beams using surface waves of light. We have more than one control knob, and we can produce electron shapes that are currently impossible in any other active device. I hope this will usher in a new era for electron microscopy, with a far better active control over electron beams.

What is it that you like to do when you aren’t working on research?
I love writing sports articles for sports blogs! Especially about basketball and the NBA. I also enjoy singing and playing role-playing games with friends, but lately I just focus on spending time with my spouse and child whenever I get the chance.

Is there enough support/funding for science in Europe today? What could be improved in this respect, at a national level? And at European level?
I do not feel I have the tools to answer this question.

Now for the big picture: what is your assessment of the current state of your area of research? (i.e. where do you see it going, what expectations for the future, etc.)
There truly is a massive effort (2 european consortia, in addition to other groups in Europe as well as the US) who are currently pursuing the goal of a spatial electron modulator using light – a device that can produce arbitrary free-electron shapes through the interaction of light and free electrons. Much as in our own consortium of SMARTelectron, there are many approaches to this challenge. Our efforts for shaping using structured near-fields appear to currently be at the forefront, but other near-field related approaches and even approaches utilizing the ponderomotive force are progressing very fast. It is too soon to determine which approach will be optimal, but this is a very exciting time in the life of a field: where visions are rigorously pursued, to become realities. I expect that the next 5 years will see a vast improvement in capabilities, and by then we will know much better how close we can potentially get to our final goal.

Shai graduated from the Technion – Israel institute of Technology in 2016, with a double B.Sc in Electrical Engineering and Physics, and is currently finishing his Ph.D Thesis on controlling the topology of light at the nanoscale and transferring it to matter. He is the recipient of the Jacobs Foundation fellowship, the Adams fellowship of the Israel Academy of Sciences and Humanities and the OSA’s Tingye Li innovation award.