Hello,

So I need some help. I am currently designing superconducting MKID resonators in Sonnet but I cannot get a high Q.
Ideally the MKID should resonant at 400MHz and have a Q greater than 10^6. I can get a half wave resonator to resonate at 400 MHz but the Q is always smaller than 1000.
Can anyone that is familiar with this kind of thing help me out?
I have set all losses (resistance, tangent loss) to zero and am using a surface inductance of 50 pH/Sq to simulate TiN.
The MKID is coupled to a two port feedline. I am using the graph of S21 to calculate Q by dividing the resonant frequency by the bandwidth. No matter what I do it seems like I cannot get a bandwidth smaller than .5 MHz.
Anyone have any tips or advice?

Thanks