Superconductivity of BaLi4 under pressure
Anne Marie J Schaeffer1, Matthew C DeLong, Zachary W Anderson
1Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112, USA.
Summary
We investigated superconductivity in BaLi4 under high pressure. Superconductivity was observed starting at 5.4 GPa, with critical temperatures (Tc) peaking at 7 K, showing complex pressure dependence above 12 GPa.
Area of Science:
- Condensed Matter Physics
- Materials Science
- High-Pressure Physics
Background:
- Barium lithium compounds (BaLi4) are potential candidates for novel superconducting materials.
- Understanding pressure-induced superconductivity is crucial for discovering new superconductors.
Purpose of the Study:
- To investigate the pressure-induced superconductivity in BaLi4.
- To determine the superconducting critical temperature (Tc) as a function of applied pressure.
Main Methods:
- Electrical resistivity measurements were performed on BaLi4.
- A diamond anvil cell was used to achieve pressures up to 53 GPa.
Main Results:
- Superconductivity in BaLi4 was first observed at 5.4 GPa with a Tc of 4.5 K.
- The Tc increased steeply to a maximum of 7 K between 5.4 and 12 GPa.
- Above 12 GPa, the pressure dependence of Tc exhibited complex behavior with sign changes in dTc/dP.
Conclusions:
- BaLi4 exhibits pressure-induced superconductivity.
- The complex pressure dependence of Tc suggests intricate electronic structure changes under high pressure.
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