مشخصات پژوهش

Unique features of nonlin ear solitary plasmon excitations in two and three dimen sional massless Dirac fluids, with respe ct to their norm al Fermi counterparts, are explor ed using the Berno ulli pseudopotential method. It is revealed that graphene, as a two dimension al Dirac fluid, possesses some uni que characteristics with respec t to the propagati on of the localized plasmon excitations, which is absent in other ordinary solids. It is also shown that the Mach number limit below/abo ve, which the localized solitar y/periodic excitatio ns propagate in a monol ayer gr aphene has a universal value independen t of the oth er envir onmental parameters such as the electron number-density and the ambient temperature. The amplitude of nonli near solitary or period ic wav es is also remarked to be independent of such parameters and depend only on the Mach-number value of the solitar y or periodic excitatio ns. These uni que hydrodynam ic wave features of the massless Dirac fluid are attributed to the remarkab le photon-l ike linear energy disp ersion in Dirac poi nts of graphene material.