Quantum optical studies of lasers and amplifiers

Theodor W. Hänsch, HERBERT WALTHER

C. H. Raymond Ooi, Sulaiman Wadi Harun, H. Ahmad

We have studied optical pulse propagation in a Raman fiber amplifier doped with a three-level medium and driven by a control laser pulse. We analyze the spatial-temporal dynamics of pulse propagation for different atomic initial conditions. The propagation of an optical pulse through the amplifier can be sustained by a control laser that induces transparency via quantum coherence, which is useful for extending the distance between optical repeaters. Under certain conditions, amplification is achieved without population inversion. The results could be useful for laser control of optical pulses in amplifiers and waveguides.

Lorenzo M. Narducci, Eduardo Jaime Quel, Jorge R. Tredicce

William M. Tulloch, T. S. Rutherford, Elanor H. Huntington +8 more

We present measurements of the power noise that is due to optical amplification in a laser-diode-pumped Nd:YAG free-space traveling-wave linear amplifier in a master-oscillator-power-amplifier configuration. The quantum noise behavior of the optical amplifier was demonstrated by use of InGaAs photodetectors in a balanced detection configuration, at a total photocurrent of 100 mA and in a frequency band from 6.25 to 15.625 MHz. The experimental results are in good agreement with predictions.

Nagaatsu Ogasawara, Ryoichi Ito

Optical memory, differential amplification and optical limiting have been experimentally achieved in an AlGaAs laser amplifier, demonstrating the feasibility of nonlinear optical signal processing using semiconductor laser amplifiers. The results of the analysis of the dynamic properties of semiconductor laser amplifiers are also presented; subnanosecond and femto-Joule switching, critical slowing down and output spiking due to self-tuning at the onset of light injection have been analyzed.

S. G. Lipson, H. Lipson, David Stefan Tannhauser