Learning Forum

[Nayem Hosen]

I want to design an optical metasurfaces. Could someone assist me in obtaining these figure(1) (transmittance intensity and phase shift) varying radius through Lumerical FDTD? I'm having difficulty composing a precise script. The second picture is my structure. The first one I need to calculate and plot.

[Taylor Robertson]

Hello Nayem,

I would refer you to the second step of the following example.

Small-Scale Metalens – Field Propagation

 

With FDTD you can simply sweep of the disk radius, using the required bandwidth to build up the images. Transmission comes directly from the monitors, but it is bit harder to unwrap the phase. See - Metamaterial S parameter extraction.

 

RCWA is an efficient way of getting these results, but requires sweeping frequency as well.

 

Best,

[Nayem Hosen]

Thanks for your reply. But how can I sweep frequency in the RCWA simulation? I tried to sweep the frecuency points parameter instead of height in the default small-scale metalens sweep that was given but showed an error. Which parameter should I use instead of the height parameter? Please help.

[Taylor Robertson]

Hello,

 

I cant actually see the error, but likely an issue with sweep or subsweep set-up. You can actually set the wavelength and frequency point in the RCWA object though this is the easiest. Then just use the sweep to cover the required geometric parameters.

[Nayem Hosen]

Thank you for your kind reply. I got the transmittance intensity graph directly from the sweep result and excitation setting as you suggest. 

But how can I get the transmittance phase graph? I tried the default script file but shown error. Is there any way to get the phase graph directly as like transmittace intensity?