Spin polarization and magnetostriction properties in superperiodic Janus twisted bilayer graphenes

The atomic and electronic structure of superperiodic vertical hybrid Janus heterostructures based on doped twisted bilayer graphenes were theoretically developed and studied using electronic structure calculations. Regularly opposed superperiodic sublattices of fluorine and aluminum adatoms were used to induce structural charge polarization, and uncompensated spin moments up to 1.05 µ_B per unit cell, caused by local intense transverse electric fields generated by ferromagnetically aligned spin polarization of entire lattices. It was shown that spin polarization of the heterostructures is mostly determined by partial carbon and fluorine electronic states localized in the vicinity of the Fermi level, whereas superlattices of Al adatoms mostly determine the rate of charge polarization, the symmetry, and intensity of the internal transverse electric field up to −0.018 e²_/Å. It was shown that proposed heterostructures may display advanced electronic spin, entanglement and magnetostriction properties perspective for various spin- and quantum-related applications.