Learning Forum

[afshiin.a]

Hello, I want to calculate the impulse response of the microring resonator using Lumerical. How is this down?
It should be noted that I obtained the impulse response through the formula of the microring resonator, but I want to use the software to obtain the impulse response of the microring resonator, and I see its result.
Thank you!!  

[Guilin Sun]

This same question has been replied in another post. You can simply add a time monitor at the output waveguide center. Later on, please only post the same question once, at one forum.

[afshiin.a]

Thank you so much, can you more explain this method? I don't know how to define the impulse in the source.?.  

[Guilin Sun]

The source uses its own pulse. the result from the time monitor is the system's impulse. Please just try and see if you get something.  

[afshiin.a]

Okay I do I have a question: Now, in the source settings, do I have to set the start and end wavelengths to one? In other words, should be zero the span? For example, if I want to apply impulse at a wavelength of 1550 nm, should the span be zero?
Thank you ?  

[Guilin Sun]

FDTD is a time-domain algorithm; using Fourier Transform, you can get broadband result in one simulation;

Even through you can set the start and stop wavelengths the same, such as 1550nm, the actual source is still a pulse, meaning a broadband signal.　Ansys Insight: FDTD 初学者： 为什么设置了单色光源，监视器却仍然记录了多波长的结果

Usually it is not necessary to use single wavelength, since it is sinusoidal, you do not need its time-domain information. But if you really want, you can create your own source signal, please refer 　https://support.lumerical.com/hc/en-us/articles/360041722614-4-level-2-electron-material-model