Quantum Institute: Visitor Schedule

The Quantum Lunch is regularly held on Thursdays in the Theoretical Division Conference Room, TA-3, Building 123, Room 121.
For more information, contact Diego Dalvit.

April 13 , 2006
12:30 PM

Francesco Intravaia,
Potsdam University- Institut For Physik

Casimir Effect And Interaction Between Surface Plasmons

Abstract

Casimir effect is one of the most intriguing predictions of the quantum field theory. Casimir force, in the simplest form, consists in the attraction of two neutral, non magnetic, parallels and plane mirrors placed in the vacuum at zero temperature. During the last years this force has been measured with modern experimental techniques. Several experiments reached an accuracy in the % range by measuring the force using either torsion-pendula or atomic force microscopes.

A very accurate experimental knowledge of the Casimir force and a comparison with the theoretical prediction is essential both from the fundamental point of view and from the technological one. The theory-experiment comparison is indeed a key point for the experiments searching for new short range weak forces predicted in theoretical unification models. Moreover the Casimir force becomes very important in Micro-Electro-Mechanical Systems (MEMS), very promising tiny devices containing metallic elements on a micron/submicron scale, because of the small distances between their elements.

In the first part of my talk I will shortly review the reasons for the fundamental interest in the Casimir effect and the most recent experiments pointing out the theory-experiment comparison. After I will illustrate the connection between Casimir effect between two metallic plane and parallel mirrors and the interaction between Surface Plasmons, evanescent field modes associated with the collective electron excitations propagating on the metal/vacuum interface. I will put in evidence a quite non-intuitive property, which shows the importance of the Surface Plasmons and brings to light a way through which one might hope reversing the sign of the force.