# 2015 CAP Congress / Congrès de l'ACP 2015

Jun 13 – 19, 2015
University of Alberta
America/Edmonton timezone
Welcome to the 2015 CAP Congress! / Bienvenue au congrès de l'ACP 2015!

## Quantum oscillation studies of quantum criticality in PrOs$_4$Sb$_{12}$

Jun 16, 2015, 9:45 AM
15m
NINT Taylor room (University of Alberta)

### NINT Taylor room

#### University of Alberta

Oral (Non-Student) / orale (non-étudiant) Condensed Matter and Materials Physics / Physique de la matière condensée et matériaux (DCMMP-DPMCM)

### Speaker

Dr Stephen Julian (University of Toronto)

### Description

PrOs$4$Sb${12}$ is a cubic metal with an exotic superconducting ground state below 1.8 K. The crystal fields around the Pr site are such that it has a singlet ground state and a magnetic triplet just 8K above the ground state. Under an applied magnetic field, the triplet splits, and the S$_z = +1$ state crosses the singlet state at easily accessible magnetic fields. In the region of the level crossing the ground state reconstructs, creating a so-called “antiferroquadrupolar” (AFQ) phase that exists at temperatures below $1$ K and magnetic fields between about $4.5$ and $12$ tesla. This state offers a rare opportunity to observe the behaviour of quantum oscillations upon crossing a phase transition. In a recent paper [$1$] we argued that the lower boundary of the AFQ phase should have exotic behaviour as T $\rightarrow 0$ K due to mixing of hyperfine states with the AFQ order. We will describe our attempts to observe this behaviour via magnetic susceptibility and quantum oscillation measurements. [$1$] A. McCollam, B. Andraka and S. R. Julian, Physical Review B 88 (2013) 075102.

### Primary author

Dr Stephen Julian (University of Toronto)

### Co-authors

Mr Aaron Sutton (University of Toronto) Dr Alix McCollam (Radboud University, Nijmegen) Dr Bohdan Andraka (University of Florida)

### Presentation materials

There are no materials yet.