H2 optimized software defined laser for quantum technologies in space

The advancement of quantum technologies in space requires precise and robust laser control to enable applications such as atomic clocks, cold atom interferometry, and optical coherent links. Conventional proportional-integral-derivative (PID) controllers, widely used in laser stabilization, suffer from performance trade-offs, manual tuning complexity, and limited adaptability in dynamic space environments. To overcome these limitations, we propose an <i>H</i>₂ optimized PID laser current controller, that offers guaranteed robustness and performance. This optimizer is implemented in our Software Defined Laser (SDL) architecture. SDL enables a low Size, Weight and Power (SWaP) laser instrument by integrating the configurability of SDR with high-speed optical modulation, meeting the laser stability and agility requirements of next-generation quantum payloads. Using the <i>H</i>₂-optimized PID controller, we achieved a 15% reduction in settling time within the &plusmn;10 kHz error band and improved the Allan variance by more than an order of magnitude across all averaging intervals within the first 10 seconds after locking.