Electromagnetic field quantization
in planar absorbing heterostructures
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V.I. Pipa

V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine,
41, prospect Nauky, 03028 Kyiv, Ukraine; e-mail: pipa1@bigmir.net

Abstract.
The quantization scheme for the electromagnetic field in planar absorbing
heterostructures has been developed. The scheme is based on the field expansion over a
complete set of orthonormal modes. We used two types of the field modes. The first one
is defined as the field created by a plane wave incident at the surface of the structure
from the non-absorbing half space. The second type of modes corresponds to the field
generated by electric current fluctuations in the absorbing media. To normalize the field
modes, the following conditions were used: 1) the time-averaged Poynting vector
attributed to the incident wave equals the density of energy flow of elementary quanta of
the field energy; 2) for the given frequency and polarization, the total time-averaged
Poynting vector equals to zero. The theory is applied to calculate the rate of spontaneous
transitions between electron subbands in a quantum well placed near the absorbing layer
that can support the surface phonon or plasmon polaritons.