TY  - JOUR
A1  - Armata, Federico
A1  - Vasile, Ruggero
A1  - Barcellona, Pablo
A1  - Buhmann, Stefan Yoshi
A1  - Rizzuto, Lucia
A1  - Passante, Roberto
T1  - Dynamical Casimir-Polder force between an excited atom and a conducting wall
JF  - Physical review : A, Atomic, molecular, and optical physics
N2  - We consider the dynamical atom-surface Casimir-Polder force in the nonequilibrium configuration of an atom near a perfectly conducting wall, initially prepared in an excited state with the field in its vacuum state. We evaluate the time-dependent Casimir-Polder force on the atom and find that it shows an oscillatory behavior from attractive to repulsive both in time and in space. We also investigate the asymptotic behavior in time of the dynamical force and of related local field quantities, showing that the static value of the force, as obtained by a time-independent approach, is recovered for times much longer than the time scale of the atomic self-dressing but shorter than the atomic decay time. We then discuss the evolution of global quantities such as atomic and field energies and their asymptotic behavior. We also compare our results for the dynamical force on the excited atom with analogous results recently obtained for an initially bare ground-state atom. We show that new relevant features are obtained in the case of an initially excited atom, for example, much larger values of the dynamical force with respect to the static one, allowing for an easier way to single out and observe the dynamical Casimir-Polder effect.
Y1  - 2016
U6  - https://doi.org/10.1103/PhysRevA.94.042511
SN  - 2469-9926
SN  - 2469-9934
VL  - 94
SP  - 104
EP  - 114
PB  - American Physical Society
CY  - College Park
ER  - 
TY  - JOUR
A1  - Intravaia, Francesco
A1  - Mkrtchian, Vanik E.
A1  - Buhmann, Stefan Yoshi
A1  - Scheel, Stefan
A1  - Dalvit, Diego A. R.
A1  - Henkel, Carsten
T1  - Friction forces on atoms after acceleration
JF  - Journal of physics : Condensed matter
N2  - The aim of this paper is to revisit the calculation of atom-surface quantum friction in the quantum field theory formulation put forward by Barton (2010 New J. Phys. 12 113045). We show that the power dissipated into field excitations and the associated friction force depend on how the atom is boosted from being initially at rest to a configuration in which it is moving at constant velocity (nu) parallel to the planar interface. In addition, we point out that there is a subtle cancellation between the one-photon and part of the two-photon dissipating power, resulting in a leading order contribution to the frictional power which goes as nu(4). These results are also confirmed by an alternative calculation of the average radiation force, which scales as nu(3).
KW  - quantum friction
KW  - non-equilibrium
KW  - atom-surface interaction
Y1  - 2015
U6  - https://doi.org/10.1088/0953-8984/27/21/214020
SN  - 0953-8984
SN  - 1361-648X
VL  - 27
IS  - 21
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  -