Electrodynamic interaction between a nanoparticle and the surface of a solid

Abstract

We study the interaction between a nanoparticle and the surface of a solid in the framework of the local-field method. Assuming that the nanoparticle is characterized by a finite nonlinear polarizability, we obtain the interaction potential that is repulsive at short range and has an attractive long-range tail. Our numerical analysis shows that this potential strongly depends on the shape and size of the particle. Further, we study the particle-surface interaction in the presence of a surface plasmon polariton propagating along the interface. It is shown that the excitation of the surface wave leads to a drastic (about one order of magnitude) increase in the binding energy. Potential applications of this effect are discussed.

Van der Waals interaction between surface and particle with giant polarizability

“…3), similar to that obtained in Refs. [7,8]. However, this minimum occurs close to R = R 0 , which is outside the applicability range of the perturbation theory.…”

“…In this paper, we show that essentially the same conclusion remains valid in the case of a particle interacting with a surface. We argue that the appearance of the repulsive component in the van der Waals force, reported in [7,8], is an artifact of the weak coupling perturbation theory.…”

“…This implies the necessity to take into account the nonlinear polarizability, which would lead to stabilization of the system. A similar setup, considering interaction of a nonlinearly polarizable ellipsoidal nanoparticle with a surface or with another nanoparticle has been recently studied in several articles [7][8][9]. According to the results of Refs.…”

“…According to the results of Refs. [7,8], nonlinearity generates repulsive contributions to the van der Waals force that become dominant at small distances and lead to the emergence of a minimum in the total van der Waals potential at distances about R 0 . However, nonlinear contributions in Refs.…”

“…However, nonlinear contributions in Refs. [7,8] have been taken into account only perturbatively. In our previous paper [9], we have considered interaction between two point-like nanoparticles with giant polarizability, and have concluded that a careful treatment of nonlinearity does not lead to repulsive forces: on the contrary, the van der Waals force is strongly enhanced at distances less or about R 0 , remaining purely attractive at the same time.…”