[Pierre, Yuhang, EleonoraP]

Since we noticed the not efficient gain margin, we decreased the gain of SHG servo to 2.25. Then the OLTF is measured and attached in figure 1.

After modification of poles and zeros of GRMC,  we implemented it. The important parameter is the transmission threshold which is -1.3V. The measured OLTF is attached as Figure2.

Notice: Always remember to give the high voltage driver an offset of roughly 20V by turning the knob on the front panel of it. This is because there seems a lower limit of high voltage driver.