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.
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)
