Magic-angle twisted bilayer graphene displays at different fillings of the four flat bands lying around charge neutrality point a wealth notable phases that include magnetic Chern insulators, whose magnetization is mostly an orbital nature and contiguous superconducting domes. Such rich phase diagram explained through positive interplay Coulomb repulsion electron coupling to twofold optical mod...

We introduce a generalized Hamiltonian describing not only all topological phases observed experimentally in Kekul\'e graphene (KekGr) but predicting also new ones. These show features like quadratic band crossing point, valley splitting, or the of conduction bands, typically induced by Rashba spin-orbit interactions Zeeman fields. The electrons KekGr behave as Dirac fermions and follow pseudor...

Linking structure is a new concept characterizing topological semimetals, which indicates the interweaving of gap-closing nodes at Fermi energy ($E_F$) with other below $E_F$. As number linked can be changed only via pair-creation or pair-annihilation, node more stable and robust than ordinary without linking. Here we propose type nodal between line (nodal surface) $E_F$ another in two-dimensio...