Hi Shreya Roychoudhury

You can see the following research:

1. Article Design of a terahertz metamaterial sensor based on split rin...

2. https://www.osapublishing.org/oe/fulltext.cfm?uri=oe-28-11-16834&id=431947

3. https://academica-e.unavarra.es/xmlui/bitstream/handle/2454/31635/Design%20of%20THz%20Metasurfaces%20for%20Thin%20Film%20Sensing.pdf?sequence=1&isAllowed=y

4. http://joam2.inoe.ro/articles/terahertz-metamaterial-absorber-with-sensing-capabilities/fulltext

5. https://www.nature.com/articles/s41598-017-01781-6.pdf?origin=ppub

I am not sure that THz spectrum is very good for virus detection. There were publications about some specific bacteria, like spirochetes, which fit THz band half-wavelengths range quite well. Particularly, there is something with ionic conductivity, if I am not mistaken, which make them a good antennae.

First of all you need specifically determine detection mechanism, then you be able to find description path. In my view, if the target virus shows distinct absorption and /or reflection versus THz radiation, you can develop a meta-surface according to target frequencies. Backing to your question regarding simulations, I have to say that several possible simulations are available to you. You can use COMSOL, CST, Lumerica and MATLAB to describe your device. Even you can use equivalent circuit model for speedier simulations. In this way you have to describe your materials and structures. For instance see:

Biabanifard, Sadegh, et al. "Tunable ultra-wideband terahertz absorber based on graphene disks and ribbons." Optics Communications 427 (2018): 418-425.

Sadegh Biabanifard

I don't think you can use Lumerical, since it is a scale/performance oriented ray-tracing software. Maxwell solutions are acqured as 2D eigenmodes for hard-bounded guides. AFAIK, It is not applicable to complex antennae-like 3D subwave structures.

In Matlab, there is no native instruments for EM simulation. But OpenEMS may provide an FDTD solver. Not very fast, but still very useful. Does not support complex anisotropy. Requires 3rd party tools for field reports.