@article{25aec86eaa1d4288bb32d426c1e43586,
title = "Ultrashort Pulse Self-Switching in Coupled-Semiconductor Traveling-Wave Amplifiers",
abstract = "We study the self-switching of picosecond pulses using an active nonlinear directional coupler formed by two semiconductor laser amplifiers. Self-phase modulation associated with gain saturation permits all-optical control of output pulses emerging from the amplifiers, but switching from the cross state to the bar state is limited to 50% of the output energy. The amplified output pulses may be switched with little temporal distortion, while considerable red shift in the output pulse spectra may occur.",
author = "Stefano Trillo and Stefan Wabnitz and Soto-Crespo, {J. M.} and Wright, {E. M.}",
note = "Funding Information: Self-switching of light in optical-fiber NLDC{\textquoteright}s has been demonstrated experimentally. Here the nonlinearity (Kerr effect) is virtually instantaneous but weak, thereby requiring high (kW) switching powers [3]-[5]. The use of semiconductor waveguides, on the other hand, permits the use of substantially lower switching powers, because of resonant enhancement of the electronic nonlinearity of wavelengths near the fundamental bandgap [6]. Switching in semiconductor NLDC{\textquoteright}s has been reported with quasi-continuous-wave, picosecond, and femtosecond excitation [7]-[ 121. The possibility of routing ultrashort pulses is clearly the most attractive characteristic of nonlinear couplers when compared to electronic devices. It appears, however, that nonlinear absorption, which accompanies nonlinear index changes in a passive semiconductor NLDC, may reduce switching efficiency substantially and, in any case, will limit the cascadability of successive couplers significantly [ 131, [ 141. Furthermore, for pulses longer than the nonlinearity (carrier) relaxation time T, temporal breakup occurs in the output pulses [4]. On the other hand, for pulsewidths much shorter than T<, Manuscript received July 26, 1990; revised October 19, 1990. This work was camed out in the framework of an agreement between the Fondazione Ugo Bordoni and the Instituto Superiore Poste e Telecomunicazioni. The work of E.M. Wright was supported by a joint program of the Air Force Office of Scientific Research and the Army Research Office (JSOP Program). The work of J. M. Soto-Crespo was supported by a grant from the Ministerio de Educacion y Ciencia, Spain. S. Trillo and S. Wabnitz are with the Fondazione Ugo Bordoni, 00142 Rome, Italy. J. M. Soto-Crespo and E. M. Wright are with the Optical Sciences Center, University of Arizona, Tucson, AZ 85721. IEEE Log Number 9143236.",
year = "1991",
month = mar,
doi = "10.1109/3.81339",
language = "English (US)",
volume = "27",
pages = "410--415",
journal = "IEEE Journal of Quantum Electronics",
issn = "0018-9197",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
number = "3",
}