Linear and Nonlinear Optical Pulsed Response of CO2 Laser Amplifiers
Abstract
The linear and nonlinear optical response of a C02 laser amplifier has been measured for pulse inputs which have risetimes shorter than or comparable to the inverse bandwidth of the medium. The pulsed response behavior was predicted theoretically by integrating density matrix equations. The theoretical linear (small-signal) response of a laser amplifier to a rectangular pulse signal input was derived. The linear step response was measured experimentally, and by comparison with the derived theoretical response, the bandwidth of the amplifier was directly measured. The amplifier response was also studied for extremely intense fast risetime pulse inputs. At low amplifier gas pressures, the output pulses had faster risetimes than the input pulses, and the lagging edge of the pulse was absorbed leading to active pulse sharpening. The amplification was not bandwidth limited. At high gas pressures, no absorption of the lagging edge was observed because of rotational relaxation. The nonlinear pulse amplification results were also predicted theoretically.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1970
- Accession Number
- ADA542546
Entities
People
- Paul W. Hoff
Organizations
- Massachusetts Institute of Technology