Interference fringes from stabilized diode lasers

摘要

Interference fringes produced by a pair of intracavity stabilized diode laser beams, each impinging separately on one aperture of a double slit, are recorded on a linear charge-coupled device array. The peculiar result of the experiment is that the fringe system is found to persist for a time of the order of 1 ms and loses contrast for longer integration times. This implies that the individual linewidths of the two beams from the stabilized lasers are narrower than 1 kHz and that the average drift rates of the central peaks are far less than 0.1 MHz/s. The device was built within the advanced undergraduate electronics laboratory of the department of physics and represents a considerable improvement over previous demonstration apparatuses used tcs detect interference fringes from independent lasers. (C) 2000 American Association of Physics Teachers. [References: 19]