Imperial College London case study

Precision Ice Bloc control of pump laser diodes for synchronised mode-locked fibre lasers

Ice Bloc is helping researchers at Imperial College London to precisely control multiple laser diodes simultaneously for developing new fibre lasers.

The Photonics Group at Imperial College London are developing new short-pulse fibre lasers for scientific and biomedical applications. This includes pump-probe spectroscopy, which requires synchronised trains of ultrashort sub-picosecond pulses at different wavelengths; from compact and reliable laser systems. Therefore, researchers are developing sources of two-colour pulses using two coupled fibre lasers, both pumped by laser diodes.

The generation of low noise and highly stable synchronised pulse trains places stringent requirements on the pump diode drivers: drive current drift or perturbations can severely degrade the quality of the fibre laser output and break synchronisation. Additionally, the use of two cladding-pumped fibre amplifiers requires two high-power laser diodes (and drivers), each operating with greater than 2A current).

Ice Bloc DD40 was ideal for this application, offering precise low-noise current control with up to 40A on four separate channels, all packaged into a single compact unit.

Additionally, Ice Bloc DD40 delivered more than just the required current for this project. It was operational in minutes after being plugged into the lab network, enabling instant wireless control through the web interface on researchers’ laptops. The ability to see the status of, and control, all laser diode channels on a single web page proved helpful for tuning the pump current to the threshold for pulse generation. Fine-tuning was also particularly easy using arrow key keyboard short cuts. Once the required current levels were established, the switch-on routine could be automated by integrating the Ice Bloc control codes into the lab’s existing instrument control software.

In summary, Ice Bloc DD40 enabled laser researchers to quickly and easily control the pump diodes in their experiments with great precision, enabling them to focus on the fibre laser design and development.