Discovery of a superhard iron tetraboride superconductor.

  title={Discovery of a superhard iron tetraboride superconductor.},
  author={Huiyang Gou and N. Dubrovinskaia and E. Bykova and A. Tsirlin and D. Kasinathan and W. Schnelle and A. Richter and M. Merlini and M. Hanfland and A. Abakumov and D. Batuk and G. van Tendeloo and Y. Nakajima and A. Kolmogorov and L. Dubrovinsky},
  journal={Physical review letters},
  volume={111 15},
Single crystals of novel orthorhombic (space group Pnnm) iron tetraboride FeB4 were synthesized at pressures above 8 GPa and high temperatures. Magnetic susceptibility and heat capacity measurements demonstrate bulk superconductivity below 2.9 K. The putative isotope effect on the superconducting critical temperature and the analysis of specific heat data indicate that the superconductivity in FeB4 is likely phonon mediated, which is rare for Fe-based superconductors. The discovered iron… Expand
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