The de Haas-van Alphen effect across the metamagnetic transition in Sr$_3$Ru$_2$O$_7$

TL;DR

This study investigates the de Haas-van Alphen effect in Sr3Ru2O7 across its metamagnetic transition, revealing mass enhancements near the transition with minimal Fermi surface changes, supporting a field-induced Stoner transition model.

Contribution

It provides detailed experimental evidence of quasiparticle mass enhancement and Fermi surface stability across the metamagnetic transition in Sr3Ru2O7.

Findings

Quasiparticle masses increase near the transition

Fermi surface topology remains largely unchanged

Results support a field-induced Stoner transition mechanism

Abstract

We report a study of the de Haas-van Alphen (dHvA) effect on the itinerant metamagnet Sr$_3$Ru$_2$O$_7$. Extremely high sample purity allows the observation of dHvA oscillations both above and below the metamagnetic transition field of 7.9 T. The quasiparticle masses are fairly large away from the transition, and are enhanced by up to an extra factor of three as the transition is approached, but the Fermi surface topography change is quite small. The results are qualitatively consistent with a field-induced Stoner transition in which the mass enhancement is the result of critical fluctuations.