Photonic Crystals

Experimental work in this area was initiated in 2004 at IIT Bombay with sponsored funding from the Department of Science and Technology, Government of India. Subsequently, this work received funding from BRNS twice, DRDO and DST. Salient results of this work:

1. Photonic crystals grown with the low-cost self-assembling techniques have shown superior stop band characteristics.
2. Three-dimensionally ordered photonic crystals using inorganic and organic colloids have been synthesized with the photonic stop band in the UV/visible/near-IR regions of the electromagnetic spectrum with broad tunable region
3. Reflectivities exceeding 70% (along with a corresponding fall in transmission) have been achieved with a careful control of growth conditions of the photonic crystals
4. Effective infiltration of the photonic crystal voids with SiO2 and ZnO by sol-gel method has been demonstrated.
5. Double photonic stop band has been obtained by the growth of photonic crystal heterostructures, with two independent materials and two different colloidal diameters.
6. Functionalized photonic crystals synthesized with organic dye-polymeric colloids have shown the simultaneous signature of the dye and the photonic crystal stop band in the laser-excited emission studies.
7. Photonic crystals with the stop band spanning the entire S, C and L bands of the optical communication region, by angle-resolved tuning, have been obtained.
8. Photonic crystal waveguides written with electron-beam lithography as well as femtosecond laser pulses.
9. Study of lasing action and lowering of threshold in a photonic crystal environment.
10. Experimental study of 2-D photonic crystals made by EBL.
11. Effect of localized surface plasmon resonance in photonic crystals infiltrated with gold nanoparticles.
12. Complete suppression of non-radiative emission in plasmonic photonic crystals.
13. All-angle negative refraction in honeycomb lattice photonic crystals.
14. Photonic crystal heterostructure-based laser cavities.
15. Replicating photonic crystals for anti-reflecting surfaces – experiment and modeling.