Can Linien + Sinara 8462 Fast Servo lock two lasers independently?

Guest

Hi,
I am considering using the Sinara 8462 Fast Servo to replace the Red Pitaya StemLab 124‑10 for laser frequency stabilization and locking.
I am currently using a Red Pitaya with PyRPL to lock two lasers independently. PyRPL provides multiple IQ and PID modules, so my current setup is roughly:
ADC1: PD signal from laser 1
ADC2: PD signal from laser 2
Two independent IQ demodulation + PID loops
DAC1 → PZT of laser 1
DAC2 → PZT of laser 2
For each DAC output, the PID correction, a 25 kHz PZT modulation signal, and a slow PZT scan/offset are summed together before being sent to the laser PZT input.
I am considering upgrading to the Sinara 8462 Fast Servo and using Linien.
My question is: Can one 8462 running Linien implement two fully independent laser locks simultaneously, i.e.
ADC1 → IQ1 → filters → PID1 → DAC1
and
ADC2 → IQ2 → filters → PID2 → DAC2
with independent modulation/demodulation phase, sweep, PID parameters, etc. for each channel?
If this is not currently supported by the standard Linien firmware, is the 8462 FPGA/gateware capable of implementing it with modifications?

My application is locking 852 nm and 509 nm lasers to Cs SAS/EIT signals, with about 25 kHz PZT modulation.

Thanks!

fsagbuya

With the current Linien implementation, this is not supported. Linien is designed around a single PID loop, using the two ADC inputs together for FMS+MTS spectroscopy, rather than providing two independent lock paths.

The Fast-Servo hardware itself has 2 ADCs and 2 DACs, so it should be capable of handling two independent locks. Supporting this would be feasible with modifications to the Linien gateware/software, such as adding a second PID loop and independent modulation, sweep, and output routing for each channel.