Abstract

Ultrafast all-optical switching has been demonstrated in various optical fibre interferometric devices using the optical Kerr effect [1-4]. The ultrafast nonlinearity of silica results in incomplete optical switching with non-square pulses (square pulses: rise time ≪ pulse width). Complete pulse switching can be achieved using soliton-like pulses and we recently demonstrated its implementation in an antiresonant nonlinear fibre Sagnac interferometer [5]. In many applications it is not possible to be in the soliton regime. For these applications we propose complete optical switching of a short signal pulse by a high power broad control pulse. The signal pulse experiences a uniform phase change if the two pulses are temporally overlapping. In addition, by suitably selecting the pulse widths of the signal and control pulses it is possible to achieve complete pulse switching even in the presence of moderate walk off between the two pulses of different wavelengths due to the group velocity dispersion.

© 1990 Optical Society of America