I measured the PZT efficiency of PMC using the same method as klog:35875, but with lower laser power in order to avoid thermal expansion at the PMC body.

I set the neoLASE current to 3A, corresponding to 2.7W. Originally, it was 7.7A, for ~30W, so the power is roughly 1/10.

As Fig.1, the difference in the shape of the carrier transmission between forward and backward, which was seen with 30W, is perfectly gone. Note that the dotted line in the normalized transmitted light shows the height of the carrier, and it is much lower than 1 because the mode matching is bad since neoLASE is operated with lower power.

10 times measurements were done for each forward and backward with such low power. The results are;

• Forward (10 times average): 162.01+/-1.01 V/FSR -> 0.9160+/-0.0056 MHz/V
• Backward (10 times average): 162.09+/-0.73 V/FSR -> 0.9154+/-0.0042 MHz/V

Both results corresponded quite well, within the error bars. If we take the average of them;

• PMC actuator efficiency: 162.05+/-0.87 V/FSR -> 0.9158+/-0.0048 MHz/V