Superconductivity in a Scandium Borocarbide with a Layered Crystal Structure

Area of Science:

• Materials Science
• Condensed Matter Physics
• Solid State Chemistry

Background:

• Recent discoveries of near room-temperature superconductivity in superhydrides spur research into conventional superconductors.
• Exploration of light-element materials is key to achieving higher critical temperatures (Tc).

Purpose of the Study:

• To investigate new superconducting phases in the scandium borocarbide system.
• To synthesize and characterize novel ternary Sc-B-C compounds for superconductivity.

Main Methods:

• Rietveld analysis for crystal structure determination.
• Density Functional Theory (DFT) calculations for chemical formula validation.
• Experimental measurements to determine superconducting properties, including critical temperature (Tc).

Main Results:

• A new ternary Sc-B-C compound exhibiting superconductivity was identified.
• The crystal structure was determined to be tetragonal (space group P4/ncc).
• Superconductivity was observed at a critical temperature (Tc) of 7.7 K, characteristic of type-II superconductors.

Conclusions:

• A novel scandium borocarbide superconductor, Sc20C8-xB xC20 (x=1 or 2), was successfully synthesized and characterized.
• Boron incorporation is crucial for stabilizing the observed crystal structure.
• First-principles calculations indicate that Sc-3d orbital contributions are primarily responsible for the observed superconductivity.