Topological superconductivity near van Hove fillings
Thursday 02 January 2025, 11:00am
Dr. Debmalya Chakraborty (Faculty Candidate), Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
Location : AB2-5B (AB2)
Abstract: Topological superconductors have become an important research topic,
stimulated by their potential for quantum and superconducting
applications. Since the topology only protects against perturbations
smaller than the superconducting gap, it is of paramount importance to
find topological superconductors with large gaps and high transition
temperatures. One possible path to high-temperature topological
superconductivity is to consider materials where the Fermi level lies
close to van Hove singularities (VHSs), which enhance the density of
states. Motivated by this, in this talk, I will show the conditions
under which topological superconductivity emerges close to van Hove
fillings on the kagome [1] and square [2] lattices. For the kagome
lattice we find that the different sublattice textures of the m-type
and p-type VHSs influence the propensity for topological
superconductivity. For both lattices our findings unravel a variety of
different topological superconducting states with characteristic
topological properties, including Majorana edge and corner modes. I
will also discuss how van Hove singularities can act as generic
platforms in the search for new topological quantum matter.
References:
[1] Xianxin Wu, Debmalya Chakraborty, Andreas P. Schnyder, and Andres
Greco, Crossover between electron-electron and electron-phonon
mediated pairing on the Kagome lattice, Phys. Rev. B 109, 014517
(2024).
[2] Pietro M. Bonetti*, Debmalya Chakraborty*, Xianxin Wu, and Andreas
P. Schnyder, Interaction-driven first-order and higher-order
topological superconductivity, Phys. Rev. B (Letters) 109, L180509
(2024). *=Equal contribution.