She spent a year in the FZU laboratories, researching structures invisible to the naked eye, and advanced to the national round of the Students’ Professional Activities (SPA). How did Lucie Krejčová work her way to such a remarkable success?
Think of ordinary magnets, the ones on your kitchen fridge. Their so-called magnetic moments all point in the same direction, which is why they attract on one side and repel on the other. But there are other magnetic materials, known as antiferromagnetic, whose magnetic moments cancel each other out. The result? The material appears completely non-magnetic on the outside, as if it were entirely ordinary.
It is precisely from such a material, a compound of copper, manganese and arsenic, that the nanowires Lucie Krejčová studied in her research are made. Thanks to their properties, they could one day serve as the basis for a new type of memory: faster, with greater capacity and more resistant to magnetic interference, which is one of the key challenges facing today's data storage.
Small, almost invisible
Lucie Krejčová focused on how to actually grow such nanowires and what can be learned about them. Verifying whether the growth was successful, however, is far from straightforward. The nanowires are so thin that an ordinary microscope simply cannot see them. Imaging them requires an electron microscope, which uses a beam of accelerated electrons instead of light.
Even with one, handling the nanowires is enormously demanding. "We have to bring a special manipulator up to the wire, attach it and only then cut it off. If we tried to simply place it on the manipulator, electrostatic forces would take over and the wire would either stick to the surface or fly off into the vacuum. That would be the end of it," Lucie Krejčová explains.
She grew the nanowires in collaboration with Jakub Strnad, who was working on the same topic as part of his master's thesis. Their team then had to verify that the wires had the correct internal structure, and the results confirmed that the material was of good quality and free of major defects. The research is not yet complete, however, and further measurements are planned for the summer, partly as a foundation for a new team member's bachelor's thesis.
A year in the lab
Lucie Krejčová has been working at FZU for two years, one of which she has spent on this particular project. She joined with no laboratory experience and initially focused on observing how her colleagues worked. "I came to the institute as a blank slate. Everything I have achieved is the result of the people around me," she says. She gives considerable credit to her supervisor Filip Křížek, who offered her the opportunity to get involved in research and has supported her professional development from the start.
The year in the lab also taught her patience. She now looks back with a smile on the moments when experiments refused to go as planned. "I spent whole days repeating the same thing over and over, and it just wouldn't work," she admits. "It was a real disappointment, but in the end it helped me learn to deal with failure."
Ahead of the national finals in Olomouc, she incorporated the feedback from the regional round and re-recorded the video defending her work. Among the best secondary school projects in the Czech Republic, she ultimately finished 4th and won the Czech Nuclear Society Award.