DFB lasers for all-optical signal processing

Research Area: Integrated lasers and LEDs , Silicon photonics for telecom, datacom and interconnect

Main Researcher: Amin Abbasi

All-optical signal-processing devices are playing an essential role in the future of optical-data networks. In order to increase the network efficiency and raise the bandwidth, all optical switching networks are desirable, because they can reduce the switching energy as well as increase speed by avoiding optical-to-electrical or electrical-to-optical signal conversion. Bistable optical devices can be used as the basis of all-optical flip-flops, in which switching happens by set and reset optical short pulses.

Schematic of the DFB laser based on flip flop operation

Our approach for the all optical flip flop switching is based on a λ/4-shifted DFB laser, which becomes bistable by injecting a master laser light, with a wavelength is outside the DFB laser stop-band. This bistability is observed in the lasing light as well as in the amplification of the external light and is due to non-linear effects having their origins in the carrier distribution (i.e. longitudinal spatial hole burning).

Bistability diagram of the flip flop system

Other people involved:

• Amin Abbasi

PhD thesises