Quantum nonlocal polarizability of spherical metal nanoparticles

Abstract

An explicit calculation of the quantum nonlocal (QNL) polarizability of a metallic nanoparticle is presented, where two quantum longitudinal plasma waves are excited. The QNL generalization of the classical Clausius–Mossotti factor of the system is derived, by means of the quantum hydrodynamic theory in conjunction with the Poisson equation and applying the appropriate additional quantum boundary conditions.