News from the group of theoretical physics
A recent ACS Nano publication (featured on a cover) shows how assemblies of radical organic molecules on a superconducting surface can host distinct quantum states. The study demonstrates that varying molecular distance and orientation alters magnetic coupling, inducing transitions between singlet and doublet ground states. This discovery provides a novel strategy for controlling and engineering quantum materials—an essential step toward future applications in quantum electronics and spintronics.
A collaborative effort featuring an international team including I. Konyashin from Element Six Group, A. Cammarata from CTU, and A. Koliogiorgos from our department, delivers a definitive description of FCC-carbon's structural and electronic properties. For decades, the characteristics of FCC-carbon remained poorly defined. This unique material has a large bandgap typical of insulators yet exhibits notable semiconductor-like conductance. Our findings introduce FCC-carbon as a novel class of quasivalent solids with unusual conductivity not previously documented.
We welcome Sachin Verma, Ph.D., as a new member of our group. We wish him a creative and productive post-doctoral stay at Charles University!
In a recent letter by Peter Zalom from FZU, Martin Žonda, and Tomáš Novotný from our department, a novel approach to understanding interacting quantum dots coupled to multiple superconducting leads, based on a so far hidden symmetry, has been unveiled. These hybrid nano systems have the potential to be used as building blocks of the future superconducting electronics devices. As also revealed in the letter, they can be tuned to serve as superconducting diodes or even transistors.
We welcome new group members: Subhasmita Ray, Ph.D., and Daniel Bobok, Mgr. Sc. We wish them interesting problems to solve, scientific breakthroughs, and productive studies during their stay at Charles University!
Congratulations to Štěpán Marek, Ph.D. on successful doctoral defence! We wish him much success in his postdoctoral position at the University of Regensburg!
The theoretical department and the department of nanostructures of KFKL participate in the the project Quantum materials for applications in sustainable technologies (QM4ST). The project was awarded from the Programme Johannes Amos Comenius co-financed by the EU, the main researcher is the University of West Bohemia in Pilsen.
Due to their infinite variability, molecular-based transistors offer an exciting alternative to the silicon technology. In collaboration with a lab in India, our theorists have described the workings of a molecular junction that is almost transparent for the electronic current. We congratulate Štěpán Marek, our Ph.D. student, for his first publication!
In contrast to silicon-based transistors, single-molecule junctions can be gated by simple mechanical means: by either stretching or pulling the electrodes. The detailed impact of gating on the conductance has to be evaluated by using quantum theory. Our team has paired with an experimental lab to understand what is going on when you stretch a single molecule.
Scientists from our faculty have made a groundbreaking discovery in the field of optoelectronics. Our research demonstrates a new way to manipulate excitons in semiconductors using coherent optical interactions, opening the door for ultrafast valleytronics operating at multiterahertz frequencies.
