Science and Technology

Article by Técnico researchers highlighted in Physical Review Letters

The article "Topologically protected quantization of work" co-authored by researchers Bruno Mera and Yasser Omar was highlighted and published in Physical Review Letters.

The starting point of the article by Bruno Mera (IT researcher), Yasser Omar (IT researcher and Técnico professor), and Krzysztof Sacha (professor at the University of Krakow), is the topological behaviour and its quantization.

“We found that the effects of the electromagnetic field varying in time with a certain periodicity and the twist in the wave function have a consequence: the atom experiences an effective electric field that has very interesting properties, namely, the average work performed by this electric field is quantized in frequency units of the initial electromagnetic field”. Since the movement of this atom contains the information about the wave function we are witnessing semi-classical dynamics, that is, an effect of quantum theory in a classical dynamic, and this is perhaps the most curious discovery of this article, published last Tuesday, July 9th.

“The amazing thing we discovered is that if we deform the system a little by changing the magnetic field or by changing the electric field, the quantization of work remains. We can change the parameters and it remains stable; it is topologically protected against the changes, therefore there is a robustness. I think this is the main conclusion of our article”, says Bruno Mera. Professor Yasser Omar agrees and stresses “having classical degrees of freedom coding quantum information is surprising”. This work opens doors to numerous and interesting possibilities from the point of view of quantum information, although at the moment they are just simple speculations of the two enthusiastic scientists.

The article was published in Physical Review Letters on 9th July. The work is largely based on theoretical physics. “The article proposes some ideas that can be developed at several levels”, stresses professor Yasser Omar.

The collaboration between the three authors of the article “Topologically protected quantization of work” was established under the European project Theory-Blind Quantum Control, in which Portugal is represented by the Physics of Information and Quantum Technologies Group at Instituto de Telecomunicações. “We had a meeting and we began to question the topological effects of professor Krzysztof Sacha’s crystals”, recalls professor Yasser Omar, stressing that the funny thing in science is this constant discovery of new problems. “Physical Review Letters is a very selective and highly regarded journal and only articles with these characteristics are published”, says professor Yasser Omar. Bruno Mera pointed out “our article was selected as Physical Review Letters Highlight. Not all articles are entitled to synopsis highlight so this shows the exceptional value of our article”. These synopses are brief summaries written by experts that highlight the scientific value of articles and can change the course of research, inspiring a new way of thinking.