Multiple triple-point fermions in Heusler compounds


Using the density functional theoretical calculations, we report a new set of topological semimetals X2YZ (X  =  {Cu, Rh, Pd, Ag, Au, Hg}, Y  =  {Li, Na, Sc, Zn, Y, Zr, Hf, La, Pr, Pm, Sm, Tb, Dy, Ho, Tm} and Z  =  {Mg, Al, Zn, Ga, Y, Ag, Cd, In, Sn, Ta, Sm}), which show the existence of multiple topological triple point fermions along four independent axes. These fermionic quasiparticles have no analogues elementary particle in the standard model. The angle-resolved photoemission spectroscopy is simulated to obtain the exotic topological surface states and the characteristic Fermi arcs. The inclusion of spin–orbit coupling splits the triple-point to two Dirac points. The triple-point fermions are exhibited on the easily cleavable (1 1 1) surface and are well separated from the surface point, allowing them to be resolved in the surface spectroscopic techniques. This intermediate linearly dispersive degeneracy between Weyl and Dirac points may offer prospective candidates for quantum transport applications.

Journal of Physics : Condensed Matter
Ravindra Shinde
Ravindra Shinde
Research Scientist

I am a theoretical and computational condensed matter physicist and quantum chemist. I am currently working as a researcher at the University of Twente, the Netherlands. I am also the founder of The Science Dev.