Temperature-dependent Fermi surface evolution in heavy fermion CeIrIn5

TL;DR

This study uses first-principles calculations to analyze how the Fermi surface in CeIrIn5 evolves with temperature, revealing a transition from localized to itinerant 4f electrons and associated changes in quantum oscillation behavior.

Contribution

It provides a theoretical analysis of temperature-dependent Fermi surface evolution in CeIrIn5 using DFT+DMFT, highlighting the interplay between localized and itinerant 4f electrons near a quantum critical point.

Findings

Quantum oscillation frequencies scale logarithmically with temperature.

Cyclotron masses show similar logarithmic scaling behavior.

Resistivity peak at 50 K results from competition between incoherent and coherent 4f electron states.

Abstract

In Cerium-based heavy electron materials, the 4f electron's magnetic moments bind to the itinerant quasiparticles to form composite heavy quasiparticles at low temperature. The volume of the Fermi surfacein the Brillouin zone incorporates the moments to produce a "large FS" due to the Luttinger theorem. When the 4f electrons are localized free moments, a "small FS" is induced since it contains only broad bands of conduction spd electrons. We have addressed theoretically the evolution of the heavy fermion FS as a function of temperature, using a first principles dynamical mean-field theory (DMFT) approach combined with density functional theory (DFT+DMFT). We focus on the archetypical heavy electrons in CeIrIn5, which is believed to be near a quantum critical point. Upon cooling, both the quantum oscillation frequencies and cyclotron masses show logarithmic scaling behavior (~ ln(T_0/T)) with different characteristic temperatures T_0 = 130 and 50 K, respectively. The resistivity coherence peak observed at T ~ 50 K is the result of the competition between the binding of incoherent 4f electrons to the spd conduction electrons at Fermi level and the formation of coherent 4f electrons.