Anomalous Shift of Chemical Potential in the Double-Exchange Systems

TL;DR

This paper investigates the anomalously large temperature-dependent shift of chemical potential in double-exchange systems using dynamical mean-field theory, considering effects like Jahn-Teller distortions and proposing measurement methods.

Contribution

It reveals the significant chemical potential shifts in double-exchange systems and discusses the impact of dynamic Jahn-Teller effects, providing new insights for theoretical models.

Findings

Chemical potential shifts significantly with temperature and magnetization.

Dynamic Jahn-Teller effects influence the chemical potential shift.

Proposes a method to measure the chemical potential shift.

Abstract

Double-exchange system is investigated by the dynamical mean-field theory. We show that the chemical potential shifts as a function of temperature and magnetization, which is anomalously large. We also discuss the influences of dynamic Jahn-Teller effect to the shift of the chemical potential. Measurement of the shift of the chemical potential casts a constraint to theoretical approaches for the magnetoresistance phenomena in ($R$,$A$)MnO$_3$ such as double-exchange effects and dynamic Jahn-Teller effects. We also propose a method to measure the shift of $\mu$.