On the high power limit of the laser linewidth
Abstract
Schawlow and Townes (1958) have studied the question of the limiting spectral linewidth of the field of a single mode laser. An equation obtained by them was subsequently modified by Yariv (1967). The present investigation has the objective to point out that, according to the modified equation, there should remain a residual laser linewidth, even as the power output P approaches infinity. In order to obtain an idea of the magnitudes involved, the case of a 0.6328 micron HeNe laser is considered. It is found that the residual linewidth dominates at power levels exceeding a few milliwatts. In a semiconductor laser the situation is found to be more complicated, because the dynamics of pumping are fundamentally different from those in a simple atomic laser.
- Publication:
-
IEEE Journal of Quantum Electronics
- Pub Date:
- June 1983
- DOI:
- 10.1109/JQE.1983.1072002
- Bibcode:
- 1983IJQE...19..889Y
- Keywords:
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- Laser Modes;
- Laser Outputs;
- Spectral Line Width;
- Helium-Neon Lasers;
- Laser Pumping;
- Semiconductor Lasers;
- Lasers and Masers