Ultrahard WB2 Superconducts under Pressure

A unique combination of high-pressure structure and transport experiments, with crystal structure simulations has  led  to  the  discovery  that  ultrahard  boride  WB2becomes a superconductor under pressure.

Superconductivity  emerges  at  55  GPa,  with  a maximum Tc of  17  K  at  91  GPa.  No  major  structural change  occurs;  instead  mechanically  induced  stacking faults and twin boundaries appear in the parent structure as  the  material  undergoes  plastic  deformation.  This unprecedented  creation  of  superconductivity  through mechanically  induced  metastable  defects  unlocks  new opportunities to look for other material systems in which metastable  structures  can  be  stabilized  in  the  form  of planar defects.

Such high-pressure synthesis provides a new route for designing ultrahard superconductors at ambient pressure through  defect  microstructures,  that  is,  exhibiting  novel properties  as  multifunctional  materials  with  applications such  as  enhanced  electrical  transport  in  extreme environments.

Additional Materials