2006/04/05 by T. N. C. Mendes, T N C Mendes, C. Farina +1
Materials Science · Physics and Astronomy · #Atom (system on chip) #Chemical and Physical Properties of Materials #Density matrix #Dipole #Energy density #Formalism (music) #Quantum Electrodynamics and Casimir Effect #Quantum and Classical Electrodynamics #Thermal #Thermal energy #quant-ph
paper · pdf · doi:10.1088/0305-4470/39/21/s51
11 pages, 3 figures
arxiv created 2006/04/05 · openalex publication_date 2006/05/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We use the density matrix formalism in order to calculate the energy level shifts, in second order on interaction, of an atom in the presence of a perfectly conducting wall in the dipole approximation. The thermal corrections are also examined when ℏω 0 / k B T = k 0 λ T ≫ 1, where ω 0 = k 0 c is the dominant transition frequency of the atom and λ T is the thermal length. When the distance z between the atom and the wall is larger than λ T we find the well-known result obtained from Lifshitz's formula, whose leading term is proportional to temperature and is independent of c , ℏ and k 0 . In the short-distance limit, when z ≪ λ T , only very small corrections to the leading vacuum term occur. We also show, for all distance regimes, that the main thermal corrections are independent of k 0 (dispersion is not important) and dependent on c , which means that there is no non-retarded regime for the thermal contributions.