Parameters of Magic-Angle Twisted Bilayer Graphene (MATBG) Superconductors

ABSTRACT

 In general, a superconducting state is described by three critical parameters, such as, critical transition temperature (T_c), critical magnetic field (H_c), and critical current density (J_c) or density of states at the Fermi surface of the superconductor. In the case of Magic-angle-twisted-bilayer-graphene (MATBG), the angle of twist between the two layers of graphene is another important parameter since the variation in  changes the value of T_c, and by virtue of the relation between T_c and E_F (Fermi energy), Constant  the value of  changes. Change in  can result in the change in density of states  , and thus it can affect the current density. Hence in MATBG, the magic angle  of twist between the graphene layers becomes an essential parameter along with the three parameters ( , , and ) that influence superconductivity in such materials, and the parameters are calculated for MATBG.

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WSN 184 (2023) 130-142

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