Thursday, March 25, 201012:30 PM - 2:00 PMT-DO Conference Room, TA-03 - Bldg 123 - Room 121|
Nonequilibrium forces between neutral atoms and surfaces
Ryan BehuninUniversity of Maryland
In this talk Iíll present a new set of techniques to describe the force between atoms, and atoms and surfaces, valid for fully nonequilibrium conditions. Iíll show how these methods can be used to describe the van der Waals force, and how they go beyond previous treatments by being valid for fully dynamical and nonequilibrium conditions. In the presence of a perfectly reflecting mirror (boundary condition on the field) an equation of motion for the atomís mean position is derived from which the atom-surface force can be obtained. Lastly, Iíll show how the atom-surface force for realistic materials can be derived by appealing to the microscopic physics of the surface elements. Integrating out the microscopic degrees of freedom of the surface leads to an effective permittivity and a stochastic source for the field. The force is then obtained through a combination of quantum and stochastic expectation values.
Host: Diego Dalvit