Carbon nanotubes (CNTs) for infrared laser systems

Carbon nanomaterials such as carbon nanotubes (CNTs) have unique optical properties that can be optimised over a very broad spectral range dependent on the size and shape of the material. They are very promising for use in non-linear optical (NLO) devices for fibre lasers to enable generation of ultrashort pulses in the infrared (IR) optical range. The IR range provides a window on to molecular composition useful in environmental or biomedical sensing applications and it is also important in telecommunications.

EU-funded scientists launched the project TELASENS (Carbon nanotubes technologies in pulsed fibre lasers for telecom and sensing applications) to exploit carbon nanomaterials in the NLO devices of pulsed fibre lasers. A particular focus is their use in saturable absorbers, NLO devices that facilitate generation of ultrashort pulses circulating in the laser resonator.

The team is making impressive progress. A combination of computer modelling and experimental physical chemistry has led to development of novel saturable absorber devices by deposition of CNTs in the fibre micro-channel and on the optical mirrors. Further, these have been integrated in fibre lasers with various active media to achieve ultrashort pulse generation in the broad (IR) spectral range between 1 000 and 2 000 nm.

Researchers are rapidly proceeding toward their end objective: development of cost-effective fibre laser sources. Eventual applications include personalised health care, novel sensors for manufacturing and transport, and new fibre optics communication systems. Along the way, TELASENS is training a new generation of scientists in NLO devices and fibre laser technologies as a legacy far outlasting the project's duration.