Photonic Crystal Lattice

[harkiranjeet kaur]

Hi
What is the main difference between Hexagonal photonic lattice and Triangular lattice as they appear almost similar? How to simulate triangular lattice in optiFDTD? Any idea, which one of these: square, hex, triangular performs best as far as losses are concerned?

[Ravil]

Hi harkiranjeet kaur,

According to your first question (as far as I can understand it), the main difference between Hexagonal photonic lattice and Triangular lattice is the geometry of the molecular lattice structure which lays beyond it. This lattice geometry can be observed with the respect to a virtual plane perpendicular to the main optical axis. According to your second question, I don’t have a lot of experience in modeling triangular lattice in OptiFDTD, so I won’t be able to give you a good advice.

[Ravil]

When you are talking about the best performance, can you, please, clarify what parameters or properties can you achieve or improve and what is your the main goal of your photonic crystals application? For example, if you are investigating birefringent properties (for such devices couplers, splitters, polarization rotators, etc.) then the crystals with biggest asymmetry should work much better. In other case, you will not need these properties, i.e. for waveguides.

[Saurav Chanda]

Hi Harikiranjeet, as far the difference is concerned they are different in geometrical shape and also with respect to irreduicable Brillouin zone along the k vector path. Simulation is you have to choose what type of crystal you want and accordingly create the defect to create any sort of waveguide. Well I would say the hexagonal arrangement is much better for propagation of modes and output power is significantly better and thus the loss is.

Thank you

[Dr. Subhashish Tiwari]

Hi,

you can take any of the structure viz. triangular, hexagonal etc.. The losses will be depending on other factors such as refractive index, core radius etc. Even I have to do the same thing.

[Ajay Vyas]

Yes, you are right subhashish. I know you are working in same field & expert for it.
Good Luck

[Dr. Subhashish Tiwari]

Thanks Sir

[harkiranjeet kaur]

Thanks for the help all.

@Ravil My circuit is add drop filter, which is a kind of coupler and splitter. For me square geometry is working the best so far if i introduce certain defects at the sharp bends. I find it quite hit and trial when simulating the circuits though.

[harkiranjeet kaur]

Do i need a separate mode solver (other than 30 bit optiFDTD version) to visualize dipole mode, quadrapole and hexpoles when simulating the resonating cavities or its just the Electric Field Distribution Curve (in the analyser) revealing all this information?

Thanks in adv.

[Author]

Posts