There is a lot of interest in finding and identifying novel
quantum materials. We here focus on d1 materials with a
strong spin-orbit coupling, which are supposed to realize a much
higher symmetry than SU(2), an emergent SU(4) symmetry [1,2].
In fact, α-ZrCl3 is expected to host the SU(4) Heisenberg model
on the honeycomb lattice with a large frustration . These
SU(4) materials potentially realize a new type of spin liquids,
a gapped Z4 spin liquid . We present new density matrix