Impact of geometrical frustration on charge transport near the Mott transition in pyrochlore (Y$_{1-x}$Cd$_{x}$)$_{2}$Mo$_{2}$O$_{7}$

TL;DR

This study investigates how geometrical frustration influences charge transport near the Mott transition in a pyrochlore compound, revealing diffusive metallic behavior driven by spin fluctuations without long-range order.

Contribution

It provides new insights into charge dynamics and spin-charge coupling in frustrated Mott insulators near the transition point.

Findings

Disappearance of spin-glass state with hole doping

Emergence of diffusive metallic transport

Strong electron mass renormalization without long-range spin order

Abstract

To search for novel spin-charge coupled phenomena in the strongly correlated electron system on a frustration lattice, charge transport and dynamics have been investigated for the hole-doped spin-glass (Mott) insulator (Y$_{1-x}$Cd$_{x}$)$_{2}$Mo$_{2}$O$_{7}$ with pyrochlore structure. Coincident with the disappearance of spin-glass state by hole doping, a diffusive metallic transport with strongly renormalized electron mass shows up with no long range spin order, which is caused by strong antiferromagnetic spin fluctuation due to the geometrical frustration.