We present an apparatus for demonstrating the Alford–Gold effect (in the more complete case of a continuous optical source) which uses only cheap commercial components such as a diode laser, a coil of optical fibers, and a photodiode. The effect is introduced on the basis of intuitive arguments; the experimental results are compared with the theoretical predictions that were first obtained by Givens and by Mandel. The demonstration turns out to be, both for graduates and undergraduates, an instructive exercise in modern coherence theory.
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© 2000 American Association of Physics Teachers.
2000
American Association of Physics Teachers
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