[Uehara, Kokeyama]

RFAMs at output beam of EOM2 were measured by Newport model 1611 yesterday. The signal amplitude for 16.88 MHz and 56.07 MHz in modulation frequency were  5 mV and  2 mV, respectively (attached). In this time, the DC voltage of the PD was 10.4 V. Two weeks ago, Nogai-kun measured RFAM for EOM1. And the RFAM was 4 mV when DC output of PD was 10.4 mV, as an example (see Nogai-kuns's post; 4033). So the measurement in this time was almost consistent with last time measurement in uncertainty. So probably EOM2 works (this topic is related to Tahara-san post; 4114).

 

And to decrease RFAM we (Kokeyama-san and me) confirmed a prodcedure;

1. input S-pol to EOM,

2. rotate a half wave plate in front of the EOM, or tilt the EOM mount (9082 etc.) . 

And find the smallest point in RFAM. That local minimum point is the best point.

 

As a  summary, when the RF of 19 dBm is inputted to EOM, 

	DC / V	RFAM / mV	PM / rad (estimated)	Comment
EOM1, f_IMC	10.4	4	? (unknown input power in this time)	an example from post4033
EOM2, f1	10.4	5	0.176
EOM2, f3	10.4	2	0.096