2012 | the 1st prototype

The main goal was to enable the packaging of cw-DFB-QCLs into TO-8 housings, and thus support their usage in mobile applications. The concept foresees the complete turn-off of the drive current between individual scans and a freely selectable duty-cycle.

Our custom-built, fully integrated, largely analog, yet flexible laser driver eliminates the need for any external electronics for current modulation, lowers the demands on power supply performance, and allows shaping of the tuning current in a wide range [1].

2016 | FPGA laser driver and DAQ system;

We exploit the benefits of the time-division multiplexed (TDM) icw driving concept and the real-time signal pre-processing capabilities of a commercial System-on-Chip (SoC, Red Pitaya). This offers a universal solution for operating a wide range of multi-wavelength QCL device types and allows stacking for the purpose of multiple laser configurations. Its adaptation to the various driving situations is enabled by numerous  FPGA functionalities that were developed on the SoC, such as flexible generation of a large variety of synchronized trigger signals and digital inputs/outputs (DIOs). The same SoC is used to sample the spectroscopic signal at rates up to 125 MS/s with 14-bit resolution.  The on-board averaging of consecutive spectral scans in real-time results in optimized memory bandwidth and hardware resource utilisation, and facilitates autonomous system operation [2].

This laser driver along with the DAQ system is used in the spectrometers produced by the Empa spin-off company MIRO Analytical AG.

2020 | Faster and better

A more powerful programmable board (Alpha250, Koheron), built around an FPGA, which features a faster sampling rate (250 MS/s) and a higher bandwidth (100 MHz) analog front end with dual-channel 14-bit ADCs and 16-bit DACs [3].

2022 | Switch-scan tuning of Vernier QCLs

This driver is specially developed for rapid switching between multiple (up to six) Vernier clusters combined with high-resolution spectral scanning within the individual clusters. Within one measurement cycle of this scheme, the current levels of the front and back heaters of the QC-XT device are stepwise modified to switch between the Vernier clusters. In parallel, we acquire many spectral scans by driving the laser in the iCW regime with a much faster repetition rate than the switching rate [4].

2024 | TDM single driver / multi-laser scheme

Stay tuned. Coming soon!