Particle-hole asymmetric lifetimes promoted by nonlocal spin and orbital fluctuations in SrVO₃ monolayers

Abstract

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 SrVO₃ 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=kF”) is known to lead to pseudogap physics. Here instead, in the multiorbital case, we evidence a differentiation between momenta on the occupied (“k<kF”) and the unoccupied side (“k>kF”) 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.