Creating shapes with sound and acoustic levitation. Asier Marzo on his research at the University of Bristol.


Asier Marzo is a research assistant at the University of Bristol in the Department of Mechanical Engineering. He gave a fascinating Science Cafe for us earlier this year on acoustic levitation.

Asier Marzo research associate at University of BristolAsier (pictured left) is interested in ultrasonics and electromagnetism and has designed several cutting-edge devices in the lab that you can recreate at home. He uses the mechanical energy carried by soundwaves to move particles and ‘shapes’ sound in the lab.

“The real research is how to trap the target particles and move them around,” explains Asier, “and we do that by shaping the acoustic field as fingers, tornadoes or bottles of loud sound; these shapes cannot be seen but can accurately move or rotate objects.”

What was it that got you interested in a career in science, where did it start?
Since I was a kid I have enjoyed opening up different devices to see how they work. Then, as soon as my brothers got a computer I was also captivated by the idea of programming it. I guess that is why I studied computer science, one of the most useful tools for research and I think for the modern-world problems. Now, with the proper tools, I am back to opening things up.

What excites you most about the work you are currently doing? And where do you see this research being used in the future?
The interesting thing about using sound to move objects is that you can work in the ultrasonic range, making the experiments harmless. Also, the wide range of sound frequencies allows us to manipulate particles ranging from tiny insects in the centimetre scale to cells of microscopic size.

Ultrasound can be used to see inside you, but it could also be used to move kidney stones, or those floaters that you get in your eye and disrupt your vision. In the future, I would love to see a medical procedure using the power of sound to not only see but to also manipulate particles inside you, from the exterior and without any incision.

Tell us about the people involved in your research – are you collaborating with anyone?
Collaboration is vital in science. I am always looking for good electronic engineers, physicists, biologist or chemists to start new projects. One collaboration is with Sussex university, where we are testing how levitated food tastes.

I am also collaborating with a biologist: we were testing to see if a levitated seed can germinate and if it presents similar characteristics as one grown in the international space station. Plants grown in low-gravity have some problems with their leaves. If the experiments carried out inside a levitator are a good representation, the experiments could be done in earth, thus reducing the cost of investigating suitable low-G crops.

The team behind Asier's research

Finally, what recent science news do you think has been the biggest breakthrough in the last year or so and why?
The landing of the SpaceX rockets was really good – in terms of engineering it was so perfect that it looked like a take-off played backwards. Also, there is something deeper in the idea of trying to colonize other planets… perhaps that we should keep looking up, aim for the starts. On a complete different scale, I also enjoyed a research paper that showed that humans can “see” individual photons. We have been a long time around and still we do not fully understand our innate capabilities!

Asier posts simplified versions of his research on where anyone can build a levitator at home with simple components. You can also follow him on Twitter to keep up with his work.