Quantum multipole radiation

The author reviews investigations of the photon localization and quantum phase problems based on the use of the representation of multipole photons. Section II presents a general consideration of the field quantization, including a comparison of zero‐point oscillations of the plane and multipole waves of photons. Section III discusses the atom‐field interaction leading to the multipole radiation. The SU(2) quantum phase representation of atomic variables is considered, as is a connection between the SU(2) quantum phase states and entanglement phenomenon. In Section IV the author describes the quantum phase of multipole radiation caused by the angular momentum conservation in the process of radiation. This approach is compared with the Pegg–Barnett formalism and with Mandel's operational approach. Section V covers the quantum polarization properties of multipole radiation. Photon localization, quantum measurements, and causality are considered in Section VI.