Transition from light diffusion to localization in three-dimensional amorphous dielectric networks near the band edge

Localization of light is the photon analog of electron localization in disordered lattices, for whose discovery Anderson received the Nobel prize in 1977. The question about its existence in open three-dimensional materials has eluded an experimental and full theoretical verification for decades. Here we study numerically electromagnetic vector wave transmittance through realistic digital representations of hyperuniform dielectric networks, a new class of highly correlated but disordered photonic band gap materials. We identify the evanescent decay of the transmitted power in the gap and diffusive transport far from the gap. Near the gap, we find that transport sets off diffusive but, with increasing slab thickness, crosses over gradually to a faster decay, signaling localization. We show that we can describe the transition to localization at the mobility edge using the self-consistent theory of localization based on the concept of a position-dependent diffusion coefficient.

PHOTONIC BAND GAP MATERIALS AND MONOLAYER SOLAR CELL

In this paper, we demonstrate theoretically an efficient way to improve the optical properties of the PIN silicon solar cell. We design an anti-reflecting coating (ARC) from one-dimensional ternary photonic crystals (PCs). Also, we design a back-reflector that composed of one-dimensional binary PC. By adding ARC layers, we have observed that the absorption is increased from 0.5 to 0.75. Moreover, by adding back reflector layers, we found that the absorption values rise to reach over 0.95 in the range of the photonic band gap (PBG) of the back reflector. Thus, using PCs in each ARC and back reflector has a significant enhancement of the absorption of the cell. Our design could have a distinct effect on the conversion efficiency of the cell. We use transfer matrix method to optimize the PBG of the back reflector. Finally, the numerical and simulated results of the cell are investigated by COMSOL Multiphysics that based on the finite element method (FEM).