Analysis of high bit rate operation of a vertically gain-clamped semiconductor laser amplifier

A detailed theoretical model of the high bit rate operation of a vertically gain-clamped semiconductor optical amplifier with high bit rate return-to-zero and non-return-to-zero input signals is presented. It is shown that good eye opening at 10-40 GBit/s can be achieved at sufficiently high operating currents (hundreds of mA in a realistic construction). A resonance between the relaxation oscillations of the vertical laser and the bit rate of the input signal is detrimental to the amplifier performance and should be avoided. When designing the length of the amplifier, a trade-off exists between the eye opening and the average gain.