  We consider an approach in which the usual wave function in the quadrature
representation of mode j of the electromagnetic field is quantized to produce a
field operator. Since the electromagnetic field is already second quantized,
this corresponds to a third quantization. This approach allows certain
calculations in quantum optics to be performed in a straightforward way in the
Heisenberg picture. Aside from being a useful computational tool, this approach
allows an interesting generalization of quantum optics and quantum
electrodynamics that could be tested experimentally.
