Abstract

The concept of coherence has been applied in the quantum theory of radiation and matter as well as in classical optics. We review here the meaning of the term in each case and show how these apparently different uses of the word coherence can be understood in terms of a single concept involving interference (nonzero cross terms), minimum uncertainty, and cohering (uniform variance) of the wave packet that describes the system. Self-induced transparency, superradiance, and superconductivity are discussed as dramatic examples of coherence.

© 1970 Optical Society of America

Coherent Modulation of a Thermal Beam*

Charles R. Willis
J. Opt. Soc. Am. 60(7) 921-924 (1970)

Buildup of Laser Oscillations from Quantum Noise

M. Sargent, M. O. Scully, and W. E. Lamb
Appl. Opt. 9(11) 2423-2427 (1970)

Mixing Partially Coherent Fields with Gaussian Irradiance Profiles; Optimization Criteria

J. N. Lahti and C. M. Nagel
Appl. Opt. 9(1) 115-123 (1970)

Resolution Testing of Coherent Optical Systems by Means of Linear Gratings

D. A. Ansley
Appl. Opt. 9(12) 2746-2752 (1970)

Theory of Optical Heterodyne Detection Using the Pyroelectric Effect

S. T. Eng and R. A. Gudmundsen
Appl. Opt. 9(1) 161-166 (1970)