News
Award for best doctoral dissertation
At the opening ceremony of the academic year of the University of Turku on September 4th, 2018, Nordita postdoctoral fellow Joonas Nättilä (astrophysics) was awarded a prize for his PhD dissertation "X-ray bursts as a tool to constrain the equation of state of the ultra-dense matter within Neutron stars". The prize, shared with Outi Veivo (French) and Nils Sandman (psychology), is awarded annually by the Turku Finnish University Society, which supports students and young researchers of the University of Turku. The prizes were handed over by the club chairman Risto Lammintausta. Nordita congratulates Joonas for this recognition of his skills as a researcher.
Outi Veivo, Nils Sandman and Joonas Nättilä.
Report from the Nordita program "Topological Matter Beyond the Ten-Fold Way"
The Nordita Program "Topological matter beyond the ten-fold way" took place July 2-27, 2018. It hosted a wide range of participants working on the frontier of topological condensed matter physics. The themes discussed during the Program encompass a broad spectrum of the subjects in the focus of research efforts in the field, from the interplay between symmetry and topology, role of interactions and disorder in topological states of matter up to realizations of topological phases in photonic and phononic systems. The discussions related to the interplay of electronic topology and crystal symmetries occupied a very prominent place during the Program.
In the top figure (taken from the talk by Titus Neupert) a manifestation of a higher order topological electronic state going beyond the ten-fold classification is shown: These are the special hinge states for a second order three-dimensional topological insulator protected by the product of a fourfold rotational and time-reversal symmetries. Systematic classification schemes and realizations of such topological states protected by various symmetries in different settings have been addressed during the Program, e.g. in phononic systems, besides more conventional crystalline non-magnetic and magnetic systems.
Experimental realizations and consequences of topological states have also been extensively discussed. As an illustration, the bottom figure (taken from the talk by Mohammad Hafezi) displays an experimentally realized photonic lattice hosting a Chern insulator. Furthermore, a zoo of different topological phases, protected by various symmetries, has been recently predicted, as discussed in many talks during the Program, but their experimental consequences, e.g. different responses, still remain to be explored. This seems to be a very prominent theme for future research in topological condensed matter and hopefully a subject of one of the future Nordita Programs.
