15 May 2019

Evidence Supporting BiPd as a Topological Superconductor

The calculated Fermi surface of BiPd projected into the first Brillouin zone.  It is complex, 3-dimensional, and composed of multiple sheets. The calculated Fermi surface of BiPd projected into the first Brillouin zone. It is complex, 3-dimensional, and composed of multiple sheets.

The observation of topological states coupled with superconductivity represents an opportunity for scientists to manipulate nontrivial superconducting states via the spin-orbit interaction. While superconductivity has been extensively studied since its discovery in 1910, the advent of topological materials gives scientists a new avenue to explore quantum matter. BiPd is being studied using "MagLab-sized fields" by scientists from LSU in an effort to determine if it is indeed a topological superconductor.

THE TOOLS THEY USED

This research was conducted in the 35 Tesla, 32 mm Bore Magnet at the DC Field Facility.

What did scientists discover?

Measured magnetization oscillations in BiPd support the assertion that it is a topologically nontrivial superconductor. This finding adds to the growing list of the unique topological properties of BiPd.

Why is this important?

The number of known topological superconductors is small. If further research confirms that BiPd is indeed a topological superconductor, this would provide a system perfect for exploring spin-orbit coupling experiments, which could provide an inroad to the manipulation of nontrivial superconducting phases.

Who did the research?

Mojammel A. Khan1, D. E. Graf2, I. Vekhter1, D. A. Browne1, J. F. DiTusa1, W. Adam Phelan1,†, and D. P. Young1

1Louisiana State University; 2National MagLab; Current address: The Johns Hopkins University

Why did they need the MagLab?

Observing de Haas-van Alphen (dHvA) oscillations in this material required MagLab-size magnetic fields. The MagLab’s torque magnetometry probe is extremely sensitive to changes in the sample’s magnetization, and its rotation capabilities allow users to map the angular dependence of dHvA oscillations. Users then compare this experimental map to the calculated Fermi Surface, which further reinforced the case for topological superconductivity in BiPd.

Details for scientists

Funding

This research was funded by the following grants: G.S. Boebinger (NSF DMR-1157490); D.P. Young (NSF DMR-1306392); I. Vekhter (NSF DMR-1410741); J.F. DiTusa and D.P.Y.(DoE SC0012432)


For more information, contact Tim Murphy.

Details

  • Research Area: Superconductivity - Basic, Topological Matter
  • Research Initiatives: Materials
  • Facility / Program: DC Field
  • Year: 2019
Last modified on 21 May 2019