Open Access. Powered by Scholars. Published by Universities.®

Electrical and Computer Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 3 of 3

Full-Text Articles in Electrical and Computer Engineering

Field-Equation Approximations And Amplification In High-Gain Lasers: Analytical Results, Lee W. Casperson Sep 1991

Field-Equation Approximations And Amplification In High-Gain Lasers: Analytical Results, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

In a related study the equations governing a high-gain laser amplifier have been solved numerically without making the usual slowly-varying-amplitude derivative approximation in Maxwell’s equations, and thus the field amplitudes are not restricted to vary negligibly in a distance of one wavelength. The results reveal an instability that involves reflections and oscillatory growth of perturbations away from steady state. In the present study steady-state solutions of the field equations are obtained analytically, and transformations are described for converting the equations to alternative intensity-equation sets. These intensity equations are linearized and solved for the growth rate and oscillation period of the …


Field-Equation Approximations And The Dynamics Of High-Gain Lasers, Lee W. Casperson May 1991

Field-Equation Approximations And The Dynamics Of High-Gain Lasers, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Semiclassical models for laser-dynamics studies typically incorporate a derivative approximation that reduces the second-order wave equation for the electric field to a first-order equation. It is shown here that this approximation and further frequency approximations are not necessary and may lead to significant errors for some high-gain laser systems. A more exact analysis also reveals a partial decoupling of the electric and magnetic fields that occurs with fast transient phenomena. These ideas are illustrated in terms of well-known dynamical effects.


Self-Pulsation Operating Regime For The Absorber Of A Twin Section Laser Diode, Gerald Farrell, P. Phelan, Joe Hegarty Jan 1991

Self-Pulsation Operating Regime For The Absorber Of A Twin Section Laser Diode, Gerald Farrell, P. Phelan, Joe Hegarty

Articles

The voltage-current characteristic of the absorber of a twin section laser diode is investigated as a function of the gain section current. For self pulsation to occur the absorber must be operated within a specific region of the voltage-current characteristics. This region only exists for absorber voltage current characteristics which contain an S-shaped negative resistance.