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Engineering Commons

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Electrical and Computer Engineering

Portland State University

Electrical and Computer Engineering Faculty Publications and Presentations

2000

Articles 1 - 2 of 2

Full-Text Articles in Engineering

Gaussian Beams In Hollow Metal Waveguides, Lee W. Casperson Jun 2000

Gaussian Beams In Hollow Metal Waveguides, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Various families of Gaussian beams have been explored previously to represent the propagation of nearly plane electromagnetic waves in media having at most quadratic transverse variations of the index of refraction and the gain or loss in the vicinity of the beam. However, such beams cannot directly represent the wave solutions for propagation in planar or rectangular waveguides, and sinusoidal mode functions are more commonly used for such waveguides. On the other hand, it is also useful to consider the possibility of recurring Gaussian beams that have an approximately Gaussian transverse profile at certain distinct planes along the propagation path. …


Power Self-Regulation In Double-Pass High-Gain Laser Amplifiers, Lee W. Casperson, Janet M. Casperson Mar 2000

Power Self-Regulation In Double-Pass High-Gain Laser Amplifiers, Lee W. Casperson, Janet M. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Double-pass laser amplifiers can provide automatic passive regulation of the power in an optical signal. This regulation can significantly reduce the amplitude noise on a laser beam that is intended as a continuous wave light source. Analytic expressions are derived to describe the optical-noise-reduction region of double-pass amplifier operation and the dependence of the self-regulation properties on gain, saturation, and mirror reflectivity.