Spectroscopic signatures of quantum friction

Juliane Klatt, Robert Bennett, Stefan Yoshi Buhmann

Published 2016-01-12Version 1

We present a general formula for the spectroscopically-accessible level shifts and decay rates of an atom moving at an arbitrary angle relative to a surface. Our Markov formulation leads to an intuitive analytic description whereby the shifts and rates are obtained from the coefficients of the Heisenberg equation of motion for the atomic flip operators but with complex Doppler-shifted (velocity dependent) transition frequencies. Our results conclusively demonstrate that for the limiting case of parallel motion the shifts and rates are quadratic or higher in the atomic velocity, and sheds light on continuing disagreements about the basic nature of quantum friction. We show that a stronger, linear velocity-dependence is exhibited by the rates and shifts for perpendicular motion, thus opening the prospect of experimentally studying the elusive phenomenon of quantum friction.