Observation of Quantum Oscillations in The Low Temperature Specific Heat of SmB$_6$

TL;DR

This study reports the observation of quantum oscillations in the low-temperature specific heat of SmB$_6$, indicating a bulk density of states origin and providing insights into its electronic structure under high magnetic fields.

Contribution

It presents the first detailed measurement of quantum oscillations in the specific heat of SmB$_6$, revealing larger effective masses and supporting a bulk origin of the oscillations.

Findings

Quantum oscillations observed in specific heat between 8 and 32 T.

Oscillation frequencies match previous torque measurements.

Effective masses are larger and consistent with zero-field specific heat.

Abstract

We report measurements of the low-temperature specific heat of Al-flux-grown samples of SmB$_6$ in magnetic fields up to 32 T. Quantum oscillations periodic in $1/H$ are observed between 8 and 32 T at selected angles between [001] and [111]. The observed frequencies and their angular dependence are consistent with previous magnetic torque measurements of SmB$_6$ but the effective masses inferred from Lifshitz-Kosevich theory are significantly larger and closer to those inferred from zero-field specific heat. Our results are thus consistent with a bulk density of states origin for the oscillations.