# Magnetic field-tuned quantum criticality in a Kondo insulator

## TL;DR

This study demonstrates that Ce3Bi4Pd3 undergoes a magnetic field-induced insulator-to-metal transition at relatively low fields, revealing a quantum critical point and providing insights into Kondo singlet formation.

## Contribution

The paper shows that Ce3Bi4Pd3 allows exploration of quantum criticality in Kondo insulators at accessible magnetic fields, linking magnetic susceptibility behavior to Kondo singlet dynamics.

## Key findings

- Identification of a magnetic field-induced quantum critical point at Bc ~ 11 T.
- Collapse of the Fermi liquid energy scale T_FL near Bc.
- Evolution of magnetic susceptibility from broad maximum to sharp transition as T approaches 0.

## Abstract

Kondo insulators are predicted to undergo an insulator-to-metal transition under applied magnetic field, yet the extremely high fields required to date have prohibited a comprehensive investigation of the nature of this transition. Here we show that Ce3Bi4Pd3 provides an ideal platform for this investigation, owing to the unusually small magnetic field of B ~ 11 T required to overcome its Kondo insulating gap. Above Bc, we find a magnetic field-induced Fermi liquid state whose characteristic energy scale T_FL collapses near Bc in a manner indicative of a magnetic field-tuned quantum critical point. A direct connection is established with the process of Kondo singlet formation, which yields a broad maximum in the magnetic susceptibility as a function of temperature in weak magnetic fields that evolves progressively into a sharper transition at Bc as T -> 0.