For more than 45 years, Laboratory Equipment magazine has been the leader in providing news on the latest new products and technologies for the lab. Every Thursday, Laboratory Equipment features a Scientist of the Week, chosen from the science industry’s latest headlines. This week’s scientist is Yaroslav Urzhumov, from Duke Univ. He and a team used a 3D printer to make an invisibility cloak.
Q: What made you interested in attempting to print an invisibility cloak?
A: I have been working on the problem of cloaking since 2006, when I first learned with fascination and awe that such a thing is possible, from the works of John Pendry, David Schurig and David Smith. I have made lots of theoretical progress since then, including a number of electrodynamics calculations proving that a limited form of cloaking is possible with non-metallic substances.
When I heard from Tom Driscoll and David Smith that they are buying a 3D printer – for other things, I instantly realized that this was my chance to demonstrate these free-of-metal, lightweight cloaks.
Q: What are the future implications of your research and findings?
A: No doubt it will find some utility in radar systems and microwave communications, both military and civilian. The most intriguing application that we like to think about is, of course, stealth - for aircrafts, vehicles, submarines and so on. And even though the current cloak prototype is not quite ready for those applications, for various reasons, I do think that our work is influencing defense engineers and causing them to think about next-generation stealth.
Amongst applications that our prototype is absolutely ready for is microwave communications through thick steal or concrete objects, which are normally non-transparent to microwaves. That and the ability of our cloak to eliminate interference of nearby objects with antennas, is perhaps the most likely immediate implication on the world.
Q: What was the most surprising thing you found in your research?
A: I found it most surprising that the most intriguing solutions sometimes come from the most straightforward approaches. In our case, the approach was to use full shape optimization of the entire structure, a technique well known in structural mechanics.
Q: What is the take home message of your research and results?
A: I think the take home message is that wild ideas become reality when several pieces of the puzzle fall properly into place. In this case, the discovery required an understanding of the cloaking theory, access to powerful computational hardware and software and the availability of inexpensive fabrication technique.
When we started designing our cloaks, we had no idea if this was going to work, and everyone was skeptical. But a) one of us – me — had a strong belief this will work, based on theoretical ideas from recent past, and b) making prototypes is so easy and cheap that it was a low-risk investment.
Q: What new technologies did you use in your lab during your research?
A: Well, the current experiment is actually a combination of several relatively well-known techniques The design algorithm is based on finite-element based optimization, as made available in COMSOL software. Fabrication uses Fused Deposition Modeling, a very cool method for making plastic objects rapidly growing in popularity.
Q: What is next for you and your research?
A: In a short term, we are definitely going to improve our plastic cloaks, to remove at least some of the limitations of the current prototype. We want to be able to cloak objects of various shapes and sizes, in a variety of microwave bands. Making them bigger without using too much material is another challenge to overcome.
In a longer term, we will be looking at other, more sophisticated fabrication techniques, which could allow us to use more than one material. As I explained, breakthroughs happen when several pieces of the puzzle come together: innovative ideas, computational powers and novel fabrication methods.