Accession Number : AD0648262

Title :   MODE-LOCKING AND MODE PROPERTIES OF OPTICAL LASERS.

Descriptive Note : Final rept., Jan-Dec 66,

Corporate Author : RAYTHEON CO WALTHAM MASS RESEARCH DIV

Personal Author(s) : Statz,H. ; de Mars,G. A.

Report Date : MAR 1967

Pagination or Media Count : 63

Abstract : The report contains: Self-Locking in Modes in Lasers and phase-locking effects between longitudinal modes in lasers. The expected phases of oscillating modes depend in a complicated manner upon the relaxation times T1 and T2 of the medium, on the degree of inhomogeneous broadening, the mode separation and location of the medium in the cavity. Simple formation of sharp output spikes at the fundamental frequency are expected where crystals like ruby or YAG are placed near the edges of the cavity. Sharp spikes at twice the fundamental frequency are expected when these solids are placed in the center of a cavity. Investigations have been completed on the mode-locking in ruby lasers where the crystals are located near the mirrors or in the center of the cavity. The observed results are in agreement with the theory. Phase-Locking of Laser Oscillators by Injected Signal and the Minimum Frequency Separation in Rotation Sensing Ring Lasers. The condition for frequency-locking of a laser oscillator by an externally injected signal is derived. The results are valid for both homogeneously and inhomogeneously broadened lines. Effects of Intensity-Dependent Anomalous Dispersion on the Mode Shapes of Fabry-Perot Oscillators. Previous work in this laboratory, as well as work by Fox and Li, has shown that the mode shapes in Fabry-Perot resonators do not change much due to the intensity-dependent saturation of the laser medium. The only effect sometimes expected with curved mirrors is that the lowest threshold oscillating mode is not the Te00 mode but one exhibiting radial nodes. However, the calculations assume that the laser oscillation is one line center. (Author)

Descriptors :   (*LASERS, *PHASE LOCKED SYSTEMS), OSCILLATION, FREQUENCY, ROTATION, DEFORMATION, SCATTERING, MIRRORS, RESONANT FREQUENCY

Subject Categories : Lasers and Masers

Distribution Statement : APPROVED FOR PUBLIC RELEASE