Lamb shift of an atom in a dielectric medium

Physical Review A - Atomic, Molecular, and Optical Physics

Volumn 59, Issue 6, 1999, Pages 4259-4263

  Milonni, Peter W ^a   Schaden, Martin ^b   Spruch, Larry ^b  

^a LOS ALAMOS NATIONAL LABORATORY   (United States)

^b POLYTECHNIC UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0001500690     PISSN: 10502947     EISSN: 10941622     Source Type: Journal    
DOI: 10.1103/PhysRevA.59.4259     Document Type: Article

References (11)

1. P.W. Milonni, J. Mod. Opt. 42, 1191 (1995).
2. M. Schaden, L. Spruch, and F. Zhou, Phys. Rev. A 57, 1108 (1998). Equation (4.8) of this paper has a typographical error; it is off by a sign. The derivation through Eq. (4.7) is correct.
3. R.P. Feynman, in The Quantum Theory of Fields, edited by R. Stoops (Wiley Interscience, New York, 1961)
4. E.A. Power, Am. J. Phys. 34, 516 (1966).
5. Feynman in his analysis was not concerned with Casimir effects. Furthermore, having assumed that only one atom was enclosed in the volume V, he took (Formula presented) to be arbitrarily small; that restriction will not be imposed here.
6. In Ref. 2, a formal expression was obtained for the sum of the Casimir and Lamb energies; the generalized argument theorem of N.A. van Kampen, B.R.A. Nijboer, and K. Schramm [Phys. Lett. 26A, 307 (1968)] was the starting point. While formally nice, it involved a complicated analysis.
7. The Feynman, Stark, and Bethe approaches to the Lamb shift, the generalized argument theorem, and various aspects of Casimir effects are discussed, for instance, in P. W. Milonni, The Quantum Vacuum (Academic, San Diego, 1994), Secs. (3.4)–(3.8) and Chap. 7.
8. M. Schaden and L. Spruch, Phys. Rev. A 58, 935 (1998).
9. The presence of (Formula presented) where (Formula presented) is the group velocity, is not surprising. Indeed, the definition of the energy density u for (Formula presented) is arrived at by considering the continuity equation, (Formula presented), where (Formula presented) is the Poynting vector, which involves the flow of energy. See, for example, Ref. 1.
10. This is true provided there are no cooperative radiative effects that can occur when the atoms are identical.
11. Considerable attention has been devoted in recent years to local field effects in spontaneous emission. See P. de Vries and A. Lagendijk, Phys. Rev. Lett. 81, 1381 (1998), and references therein.