7G20.10 - Laser Polarization & Intensity Fluctuations - Modes

Code Number:
Demo Title:
Laser Polarization & Intensity Fluctuations - Modes
Atomic Excitation and Emission
Area of Study:
Modern Physics, Lasers
One Polarizer and Lasers that are Polarized or Circular Polarized.

Turn on the laser and allow it to warm up.  Place the polarizer in the beam path and demonstrate that the polarized beam can be passed or shut off by turning the polarizer.  Circular polarized lasers will give a fluctuating beam intensity without turning the polarizer.  Beam intensities may be measured with the power meter.

  • Edwin R. Jones, "Polarization of a Helium-Neon Laser", TPT, Vol. 34, #6, Sept. 1996, p. 346.
  • Jes Henningsen, "Teaching Laser Physics by Experiment", AJP, Vol. 79, #1, Jan. 2011, p. 85.
  • Alessandro S. Villar, "The Conversion of Phase to Amplitude Fluctuations of a Light Beam by an Optical Cavity", AJP, Vol. 76, #10, Oct. 2008, p. 922.
  • Åsa M. Lindberg, "Mode Frequency Pulling in He-Ne Lasers", AJP, Vol. 67, #4, Apr. 1999, p. 350. 
  • G. A. Woolsey, M. Yusof Sulaiman, and Maarof Mokhsin, "Correlation of Changes in Laser Tube Temperature, Cavity Length, and Beam Polarization for an Internal-Mirror Helium-Neon Laser", AJP, Vol. 50, #10, Oct. 1982, p. 936.
  • I. S. Ruddock, "Analysis of Laser Mode Phases by Interferometry", AJP, Vol. 49, #12, Dec. 1981, p. 1184.
  • E. Fortin and D. Singh, "Polarization and Intensity Fluctuations in He-Ne Lasers", AJP, Vol. 49, #9, Sep. 1981, p. 891.
  • I. S. Ruddock, "Experimental Studies of the He-Ne Laser: Resonators and Self-Locking", AJP, Vol. 48, #10, Oct. 1980, p. 873.
  • P. A. Casabella, T. Gonsiorowski, and A. Leitner, "Ultrahigh and Audio Frequencies in a Laser Beam", AJP, Vol. 48, #5, May 1980, p. 393.
  • Bob Curry, "Lasers ala Mode or Modes ala Lasers", PIRA News, Vol. 8, #2, Sept/Oct. 1993, p. 16.
  • Chandrasekhar Roychoudhuri, Robert H. Noble, ""Demonstrations using a Fabry-Perot. II. Laser modes display", AJP, Vol. 43, #12, Dec. 1975, p. 1057.
  • David A. Robinson, "Detector for axial laser modes", AJP, Vol. 43, #7, July 1975, p. 652.
  • "8.3. Brewster Window for a Laser", Unknown Reference, p. 418.

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