The energy spectrum of electromagnetic normal modes in dissipative media: Modes between two metal half spaces

• The energy spectrum of electromagnetic normal modes plays a central role in the theory of the van der Waals and Casimir interaction. Here we study the modes in connection with the van der Waals interaction between two metal half spaces. Neglecting dissipation leads to distinct normal modes with real-valued frequencies. Including dissipation seems to have the effect that these distinct modes move away from the real axis into the complex frequency plane. The summation of the zero-point energies of these modes render a complex-valued result. Using the contour integration, resulting from the use of the generalized argument principle, gives a real-valued and different result. We resolve this contradiction and show that the spectrum of true normal modes forms a continuum with real frequencies.

Nyckelord

NATURAL SCIENCES

NATURVETENSKAP

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)