Participant : Eleonora, Marco, Yuhang and Matteo.

After put the first lens(f = 62.9mm), I checked the beam diameter by beam profiler. The result is 101um and 88um. According to the simulation, it should be 88um. It looks fine, so I procced.

For Faraday:

    1. Rotate lambda/4 to find the maximum, then rotate 180 degree, compare to find a better angle.(146 degree)

    2. Rotate lambda/2 to find the maximum.(279 degree)

    3. Before FI the power is 272mW, after FI the power is 253mW. The coupling is 93%.

After putting the second lens, we measured the beam is collimated and has a beam diameter as 2500um.

Then we rotate the half wave plate(163.5 degree), we have s-polarization 202mW while p-polarization 100uW. Means we have 99.95% s-polarization.

After put the 98:2 beam splitter, we got 1.9mW as transmission and 217mW as reflection. The ratio between them becomes 99 : 1. The ratio change is because of the polarization.