In fall 2020 we had our initial discussions about upgrading our laser system. Based on previously published work[1], Osama Elagabori(junior at the time) started working on the construction of the new ECDL design.
This design has two significant improvements over our current ECDL design. This new design is supposed to be more mechanically stable and also this new design has a fixed direction output beam. We finished constructing the new laser by the end of spring 2021. However, one major challenge we faced was the unexpected frequency drifts of the new laser. Eventually, we learned partial of the reason for these frequency drifts is the temperature instability of our spectrum analyzer. Drifts of the response function of the spectrum analyzer we misidentified as frequency drifts of the laser. We solved the issue with the etalon using an external temperature stabilization circuit. Even though there are some more improvements to be done, now Carla looks good and ready to excite molecules.
[1] C. J. Hawthorn, K. P. Weber, and R. E. Scholten, “Littrow configuration tunable external cavity diode laser with fixed direction output beam”, Review of Scientific Instruments 72, 4477-4479 (2001) https://doi.org/10.1063/1.1419217