The concepts of photons and photodetection are examined in a unified manner by a careful construction of localized-photon creation and annihilation operators. Photons are shown to be localizable in their direction of propagation. An ideal but realistic photodetector is shown to sense the localized photons. It is found that a photodetector with a finite bandwidth may give a small but non-zero mean photocurrent in the vacuum.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Nuclear and High Energy Physics