The two-dimensional nature of engineered transition-metal ultrathin oxide films offers a large playground of yet to be fully understood physics. Here, we study pristine ${\mathrm{SrVO}}_3$ monolayers that have recently been predicted to display a variety of magnetic and orbital orders. We find that nonlocal magnetic (orbital) fluctuations lead to a strong (weak to moderate) momentum differentiation in the self-energy, particularly in the scattering rate. In the one-band 2D Hubbard model, momentum selectivity on the Fermi surface (“$k=k_F$”) is known to lead to pseudogap physics. Here instead, in the multiorbital case, we evidence a differentiation between momenta on the occupied (“$k<k_F$”) and the unoccupied side (“$k>k_F$”) of the Fermi surface. Based on the dynamical vertex approximation, and introducing a “binaural fluctuation diagnostics” tool, we advance the understanding of spectral signatures of nonlocal fluctuations. Our work calls to (re)examine ultrathin oxide films and interfaces with methods beyond dynamical mean-field theory and may point to correlation-enhanced thermoelectric effects.

• Received 19 January 2022
• Accepted 6 September 2022

DOI:https://doi.org/10.1103/PhysRevResearch.4.033253

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Published by the American Physical Society