2007/07/31 by Daniel Braun, John Martin
Physics and Astronomy · #Advanced Frequency and Time Standards #Cold Atom Physics and Bose-Einstein Condensates #Quantum optics and atomic interactions #quant-ph
paper · pdf · doi:10.1103/physreva.77.032102
published as Phys. Rev. A 77, 032102 (2008) · 24 pages, 4 figures; improved discussion on the limitations of the theory
arxiv created 2007/10/26 · openalex publication_date 2008/03/10 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study a two-level atom in a double-well potential coupled to a continuum of electromagnetic modes (black-body radiation in three dimensions at zero absolute temperature). Internal and external degrees of freedom of the atom couple due to recoil during emission of a photon. We provide a full analysis of the problem in the long wavelengths limit up to the border of the Lamb-Dicke regime, including a study of the internal dynamics of the atom (spontaneous emission), the tunneling motion, and the electric field of the emitted photon. The tunneling process itself may or may not decohere depending on the wavelength corresponding to the internal transition compared to the distance between the two wells of the external potential, as well as on the spontaneous emission rate compared to the tunneling frequency. Interference fringes appear in the emitted light from a tunneling atom, or an atom in a stationary coherent superposition of its center-of-mass motion, if the wavelength is comparable to the well separation, but only if the external state of the atom is post selected.