Nano Express

Nanoscale Research Letters

, 5:741

First online:

Open Access This content is freely available online to anyone, anywhere at any time.

Resonant Photonic States in Coupled Heterostructure Photonic Crystal Waveguides

  • J. D. CoxAffiliated withDepartment of Physics and Astronomy, The University of Western Ontario Email author 
  • , J. SabarinathanAffiliated withDepartment of Electrical and Computer Engineering, The University of Western Ontario
  • , M. R. SinghAffiliated withDepartment of Physics and Astronomy, The University of Western Ontario


In this paper, we study the photonic resonance states and transmission spectra of coupled waveguides made from heterostructure photonic crystals. We consider photonic crystal waveguides made from three photonic crystals A, B and C, where the waveguide heterostructure is denoted as B/A/C/A/B. Due to the band structure engineering, light is confined within crystal A, which thus act as waveguides. Here, photonic crystal C is taken as a nonlinear photonic crystal, which has a band gap that may be modified by applying a pump laser. We have found that the number of bound states within the waveguides depends on the width and well depth of photonic crystal A. It has also been found that when both waveguides are far away from each other, the energies of bound photons in each of the waveguides are degenerate. However, when they are brought close to each other, the degeneracy of the bound states is removed due to the coupling between them, which causes these states to split into pairs. We have also investigated the effect of the pump field on photonic crystal C. We have shown that by applying a pump field, the system may be switched between a double waveguide to a single waveguide, which effectively turns on or off the coupling between degenerate states. This reveals interesting results that can be applied to develop new types of nanophotonic devices such as nano-switches and nano-transistors.


Photonic crystal heterostructures Nonlinear photonic crystals Photonic crystal waveguides Nanophotonics Resonant tunneling Coupled waveguides