The discovery of quantum materials requires an experimental verification of their band-structure. Quasiparticle interference (QPI) imaging with the scanning tunneling microscope can provide insight into the material’s properties when angle resolved photoelectron emission spectroscopy would be limited due to low-temperature, magnetic field or too small devices. However, obtaining band-structure insight from QPI is very slow. Our method achieves several orders of magnitude faster mapping by a mutually beneficial combination of sparse sampling and parallel spectroscopy whose effect exponentially amplify another. Our method cuts down the mapping time from weeks to minutes, enabling the faster characterization of materials and exploration of previously impossibly larger parameter spaces.

“Fast spectroscopic mapping of two-dimensional quantum materials”, Berk Zengin, Jens Oppliger, Danyang Liu, Lorena Niggli, Tohru Kurosawa, and Fabian D. Natterer, Phys. Rev. Res. 3, L042025 (2021) https://doi.org/10.1103/PhysRevResearch.3.L042025