Oxford University Press eBooks

Laser Beams

Helmut Satz

Published Feb 14, 2020• 0 citations

Abstract

In atoms, the electron orbits around the nucleus are quantized, occur for discrete energies. Transitions between energy levels require absorption or emission of photons. In the case of an unusual occupation of excited levels, individual photons can trigger a coherent transition of all such levels to the ground state, thus leading to a beam of coherent photons, a laser beam.

DOI: 10.1093/oso/9780198853398.003.0011

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