Roxanne Tutchton | Searcharxiv

arXiv2026

Effect of Electron Correlation on the Integer Quantum Hall Effect

We numerically investigate the effect of electron correlation on the integer quantum Hall effect in a square lattice. Increasing the correlation strength via the effective onsite repulsion parameter $U$ degrades the quantization of $ν= 1$ transverse conductance due to the interplay of correlation and the external magnetic field, which together induce periodic modulations in renormalized hopping parameters and site energies. Overall, this work demonstrates that the strength of electron correlation can significantly impact conductivity in the integer quantum Hall regime.

cond-mat.str-el↗

arXiv2019

Electronic Correlation Induced Expansion of Compensated Electron and Hole Fermi Pockets in delta-Plutonium

Plutonium is a critically important material as the behavior of its 5f-electrons stands midway between the metallic-like itinerant character of the light actinides and localized atomic-core-like character of the heavy actinides. The delta-phase of plutonium (delta-Pu), while still itinerant, has a large coherent Kondo peak and strong electronic correlations coming from its near-localized character. Using sophisticated Gutwiller wavefunction and dynamical mean-field theory correlated theories, we study for the first time the Fermi surface and associated mass renormalizations of delta-Pu together with calculations of the de Haas-van Alphen (dHvA) frequencies. We find a large (200%) correlation-induced volume expansion in both the hole and electron pockets of the Fermi surface in addition to an intermediate mass enhancement. All of the correlated electron theories predict, approximately, the same hole pocket placement in the Brillouin zone, which is different from that obtained in conventional density-functional band-structure theory, whereas the electron pockets from all theories are in, roughly, the same place.

cond-mat.str-el↗