Fujitsu achieves 40Gbps optical fibre transmission

FUJITSU LABS have produced optical-fibre transmission technology capable of transmitting at 40Gbps, which uses less than half the power consumption of a commercialised transmitter and requires no cooling.

The development is based around an un-cooled directly-modulated laser. This type of laser is a light source for communications that modulates intensity of light output by varying input current to a semiconductor laser. Fujitsu's new laser negates the need for a thermoelectric controller, allowing it to be more compact and operate on less power.

The active layer of the laser that produces the light is made of aluminium-gallium-indium-arsenide (AlGaInAs). This material chosen for the structure is especially suited to high speed operation.

According to Fujitsu this development is the world's first successful 40Gbps single-mode optical fibre transmission over 5km for a directly-modulated laser featuring an operation temperature range of 25°C to 70°C. µ