Abstract
We fabricated a photonic bandgap material consisting of a stack of containers with steel spheres. In the absence of external magnetic field the particles are in the disordered state. Magnetic field magnetizes the particles and they self-assemble into ordered crystalline state. We study mm-wave transmission through the stack as a function of magnetic field, i.e. for different degrees of order. This system exhibits a well-defined stopband in the ordered state, while in the disordered state the stopband becomes completely smeared. We model our results using the effective-medium approximation. We relate the disappearance of the stopband in the disordered state to the fluctuations in refraction index and admittance of individual layers. These fluctuations arise from the in-plane density fluctuations. Magnetic field suppresses density fluctuations and thus controls electromagnetic wave propagation through the stack.
| Original language | English |
|---|---|
| Pages (from-to) | 13-20 |
| Number of pages | 8 |
| Journal | Proceedings of SPIE - The International Society for Optical Engineering |
| Volume | 5218 |
| DOIs | |
| State | Published - 2003 |
| Event | PROCEEDINGS OF SPIE SPIE - The International Society for Optical Engineering: Complex Mediums IV: Beyond Linear Isotropic Dielectrics - San Diego, CA, United States Duration: 4 Aug 2003 → 5 Aug 2003 |
Keywords
- Magnetic field
- Photonic crystals
- Self-assembly
- Tunability
- Wave propagation in random media