6 papers
Observation of ring states in a delicate topological insulator
Caroline Tornow, Julia Rupprecht, Pascal Engeler +4
Topological insulators are typically characterized by particularly stable properties, such as global invariants, and can be identified by probing their robust surface states. A rec…
Stability of flat-band Bose-Einstein condensation from the geometry of compact localized states
Kukka-Emilia Huhtinen
We consider Bose-Einstein condensation in flat-band models from a real-space perspective. Using a basis of compact localized states, we reformulate the minimization of the mean-fie…
Interplay of local and global quantum geometry in the stability of flat-band superfluids
Kukka-Emilia Huhtinen, Matteo Dürrnagel, Valerio Peri +1
Quantum geometry strongly impacts physical properties in flat-band systems. We consider its role in bosonic condensation and superfluidity on flat bands, and show that the superflu…
Superfluid stiffness of superconductors with delicate topology
Tijan Prijon, Sebastian D. Huber, Kukka-Emilia Huhtinen
We consider superconductivity in two-dimensional delicate topological bands, where the total Chern number vanishes but the Brillouin zone can be divided into subregions with a quan…
Quantum geometry in superfluidity and superconductivity
Sebastiano Peotta, Kukka-Emilia Huhtinen, Päivi Törmä
We review the theoretical description of the role of quantum geometry in superfluidity and superconductivity of multiband systems, with focus on flat bands where quantum geometry i…
Flat-band ratio and quantum metric in the superconductivity of modified Lieb lattices
Reko P. S. Penttilä, Kukka-Emilia Huhtinen, Päivi Törmä
Flat bands may offer a route to high critical temperatures of superconductivity. It has been predicted that the quantum geometry of the bands as well as the ratio of the number of…