Learning Forum

[Vahram Voskerchyan]

I am trying to calculate the Q factor for the cavity that I have and I get the accurate Q factor which is around 300k.

I am using high Q analysis tool to calculate it. How can I increase the number of points for the Q factor plot. Increasing the number of time monitors give much lower Q factor which is 16k. And changing the number of frequencies doesn't affect the resolution. I want to understand how the placement of the time monitors affect the simulation (number, positioning), and why with 4 monitors it gives me the right resultls but when I increase the number of monitors it is wrong. I am following the example from here:
https://optics.ansys.com/hc/en-us/articles/360041611774-Quality-factor-calculations-for-a-resonant-cavity

Thank you!

 

[Amrita Pati]

Hi Vahram, 

Sorry, I just saw that this post hasn't been replied to. The calculation of the Q-factor is very sensitive to the simulation parameters. As mentioned in the article you have shared: "It is often a good idea to add a few point monitors at different locations to reduce the chances that a monitor is placed at a node in the mode profile of a cavity mode yielding a weak signal." I would suggest placing time monitors throughout the cavity. You can also look at the frequency monitors to ensure that you are placing the monitors where the fields are confined.

About the resolution, I believe the plot you have shown is the quality factors (Q-factor vs resonant frequency) of the resonances found (using findresonances script command) in the frequency ranges specified by the High-Q analysis group. So, if you are not changing the frequency range (or other simulation parameters), then you can not change the resolution, as the the number of resonances will remain unchanged. But let me double-check this internally.

Regards,
Amrita

[Vahram Voskerchyan]

Thank you Amrita!