Everyday choices: Viktar Asadchy, how do you control light?

How do you control light?

Actually, it’s not just me – controlling light is something we all do every day, whether by turning on a lamp, closing our eyes, wearing sunglasses or taking a photo. 

At the fundamental level, light is controlled through its interaction with materials. When light encounters a material, it causes the electrons in that material to move, creating new sources of light. By understanding and manipulating these interactions, we can design materials that guide light in specific ways. This principle is behind technologies like lenses, mirrors and even advanced optical devices.

When we talk about light, people usually think of its visible frequencies. But all electromagnetic waves have the same nature as light. So, with new materials, we can control microwave radiation, terahertz radiation or radio waves, too.

What are the benefits of controlling light?

The ability to manipulate light has vast applications. If we look at the past 120 years, about 20 Nobel Prizes in physics have been awarded for advancements in controlling light.

In practical applications, light-based technologies are used in, for example, laser systems, medical imaging, telecommunications, and even augmented reality (AR) and virtual reality (VR) glasses. The study of light leads to more efficient displays, light sources and communication networks, as well as new ways to interact with the digital world – just to name a few benefits. 

In your research, you focus on developing artificial materials that control electromagnetic waves. Why do we need new materials?

Naturally occurring materials can control light in certain ways, but they have limitations. That’s why we develop artificial materials, known as metamaterials. Instead of simply mixing materials chemically or physically, we can structure them in space at microscopic scales, creating unique properties. This way we can make optical devices smaller, more efficient and more versatile.

For example, we can design ultra-thin lenses to replace bulky camera optics or even create invisibility cloaks by bending light around objects. One recent promising application is metamaterial-inspired “smart walls” that enhance signal strength by directing electromagnetic waves precisely where needed, improving connectivity in urban environments. 

What is your greatest dream as a researcher?

When I was younger, I had an ambitious – and now I can say also a bit silly – dream to discover a new type of fundamental interaction in physics. All known forces in physics are categorized into four types: weak and strong nuclear interactions, gravitational forces, and electromagnetic forces. My dream was to find a new force that didn’t fit into any of these categories.

Now, my dream is more grounded in reality. I want to make discoveries that lead to real-world applications within my lifetime – something that can be implemented in industry within the next 20 or 30 years. Seeing my research contribute to technology and improve people’s lives would be the greatest achievement.

What fascinates you about electrical engineering and optics?

What I love about these fields is that they sit at the intersection of abstract theoretical physics and real-world applications. Abstract thinking is required to understand the principles of something we usually can’t detect with our own eyes – electromagnetic waves. But at the same time, we can conduct experiments and see direct applications of our work in the world. 

This article has been published in the Aalto University Magazine issue 35 (issuu.com), May 2025.