A Single-Photon Double-Slit Interference Experiment

American Journal of Physics

Volumn 39, Issue 4, 1971, Pages 420-424

  Parker, Sherwood ^a  

^a UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0041718523     PISSN: 00029505     EISSN: 19432909     Source Type: Journal    
DOI: 10.1119/1.1986168     Document Type: Article

References (10)

1. R. Feynman, R. Leighton, and M. Sands, The Feynman Lectures on Physics (Addison-Wesley, Reading, Mass., 1963), Vol. 1, p.37-2.
2. The first experiment that showed diffraction patterns remained unchanged at low light intensities was by G. I. Taylor [Proe. Cambridge Phil, Soc. 15, 114 (1909)]:… Photographs were taken of the shadow of a needle, the source of light being a narrow slit placed in front of a gas flame. The intensity of the light was reduced by means of smoked glass screens…. The longest time was 2000 hours or about three months. In no case was there any diminution in the sharpness of the pattern…. that longest exposure the photon density was less than 10-5 Photons/cm3!
3. Such an experiment is described in R. H. Biser, Amer. J. Phys. 31, 29 (1963).
4. He uses a cooled photomultiplier and more elaborate equipment. A PSSC film by John King showing the scanning of an interference pattern at low light levels is reviewed in M. Correll, Amer. J. Phys. 30, 772 (1962).
5. These labs are described in Forrest Mozer, Physics 4D Laboratory Manual (unpublished). Much of the spirit of this course, in which beginning students are brought in contact with significant experiments and modern equipment, comes from A. Portis, Laboratory Physics, Berkeley Physics Laboratory (McGraw-Hill, New York, 1966).
6. The Cornell Interference and Diffraction Slitfilm Demonstrator is a slide containing various single and multiple slits. It is available from the National Press, Palo Alto, Calif. See also Seville Chapman and Harold Meese, Amer. J. Phys. 25, 135 (1957).
7. A superb discussion of coherence, interference, and the uncertainty principle can be found in F. Crawford, Berkeley Physics Course (McGraw-Hill, New York, 1968), Vol. 3, pp. 427–436, 453–490.
8. Robert Swank, Ann. Rev. Nuc. Sci. 4, 114 (1954),
9. Robert Swank, Ann. Rev. Nuc. Sci. 4, 114 (1954), G. T. Wright, Proc. Phys. Soc. (London) B68, 929 (1955).
10. Whether neutral density filters or crossed Polaroids are used to attenuate the source intensity, the light from either to the slits must also be (and is) coherent in phase as well as equal in amplitude. The individual Polaroid or filter atoms constitute a secondary source of light that is driven by the primary source and reradiates, coherently, part of the incident light. The requirement of coherence at the double slits puts a limitation on the width of the primary source itself since the population of excited atoms and the phase of their radiation changes randomly in times comparable to r coh. An illuminating discussion of this point is found in F. Crawford, Ref. 9, pp. 470–473.