R&D (FilterCavity)
YuhangZhao - 18:32, Wednesday 11 July 2018 (879)
Power budget for green mode cleaner(MC)

Participiant: Yuefan and Yuhang

Today we locked the MC and Mach-Zehnder(MZ). We found some problems while locking.

1. The lock of MC sometimes has drifting. It brings the locking point to a lower point.

2. The error signal for MZ locking has a fixed frequency oscillation.

3. Sometimes we can see the MC transmission goes away very large.

We tried to make sure the MC transmission has the same level and then make the measurement.

input(unlock) 27.51mW 0.002
reflec(lock) 11.96mW 0.002
trans(lock) 12.17mW 0.007
end mirror loss 0.814mW Nan

The second cloumn is the averange power. The third cloumn is the standard deviation normalized by the averange power.

Note: the end mirror loss is diffcult to measure, so I take only one measurement.

So reflection is 43.48%, transmission is 44.24%, end mirror tans is 2.96%. We loss 2.56mW (9.32%).

Comments related to this report
YuhangZhao - 19:10, Thursday 12 July 2018 (882)

I mwasured the power loss due to detection point is not exactly the point of reflection and transmission.

For reflection, we lose 1%(0.12mW) of power. For transmission we lose 0.8%(0.097mW) of power.

So the loss of 2.56mW cannot be explained by this.