Chiral spin-orbital liquids with nodal lines

Understand

Strongly correlated materials with strong spin-orbit coupling hold promise for realizing topological phases with fractionalized excitations.

• Here we propose a chiral spin-orbital liquid as a stable phase of a realistic model for heavy-element double perovskites.
• This spin liquid state has Majorana fermion excitations with a gapless spectrum characterized by nodal lines along the edges of the Brillouin zone.
• We show that the nodal lines are topological defects of a non-Abelian Berry connection and that the system exhibits dispersing surface states.