Ion trap inside a microwave cavity

[Malamala]

I am thinking of placing an ion trap (0.3 mm rods radius, 0.6 mm from the axis and 1-2 mm long) inside a MW cavity at 100 GHz (assume the length of the cavity is 3-10 times the wavelength). What are some issues I need to consider while designing this? One main one is the drop in finesse of the cavity when placing the rods there. How can I estimate this? Also, what else should I look into? Thank you!