Ultrafast nonlinearities in semiconductor laser amplifiers

Ultrafast dynamics of quantum-dot semiconductor optical amplifiers

We report on a series of experiments on the dynamical properties of quantum-dot semiconductor optical amplifiers. We show how the amplifier responds to one or several ultrafast (170 fs) pulses in rapid succession and our results demonstrate applicability and ultimate limitations to application of quantum-dot amplifiers in e.g. amplification of signals in a telecommunications system. We also rev...

Ultrafast laser-triggered field ion emission from semiconductor tips

We study experimentally and theoretically the controlled field evaporation of single atoms from a semiconductor surface by ultrafast laserassisted atom probe tomography. The conventional physical mechanisms of field evaporation cannot explain the experimental results recently reported for such materials. A new model is presented in which the positive dc field leads to band bending with a high d...

Spectral broadening in ultrafast semiconductor optical amplifiers induced by gain dynamics and self-phase modulation.

We investigate experimentally the self-phase modulation (SPM) induced by gain dynamics on picosecond pulses in semiconductor optical amplifiers whose gain recovery is enhanced by amplified spontaneous emission (ASE). The observed pulse spectra are highly asymmetric at low drive currents but become more symmetric with increasing current, owing to the ASE-induced reduction in the gain-recovery ti...

Using Semiconductor Optical Amplifiers

Semiconductor optical amplifiers are used for efficient wavelength conversion up to 4 Gb / s. The rise and fall time as well as extinction ratio are experimentally analyzed. System performance at 4 Gb / s is evaluated showing a penalty of only 1.5 dB for the converted signal for conversion over 17 nm.

Ultrafast Semiconductor Quantum Optics