PBG structures

Here huat is the energy of the atomic transition frequency, at and aw are, respectively, the creation and annihilation operators of the field mode at frequency lo, p(u) is the mode density of the PBG structure, n(ui) and n(i are the coupling rates to the atomic dipole of a mode from the continuum and the... 

In preliminary work by the Fauchet group [32], electron-beam lithography was used to fabricate a 2D PBG structure in silicon (Fig. 12), consisting of a hexagonal... 

Calculations conducted on the 2D PBG structure suggested that the detection limit of the device was on the order of 2.5 fg of target, assuming a uniform coating on the surface of the pores, and a minimum detectable shift of 0.1 nm. Already impressive, this improves stUl further if target capture is confined to the defect hole... 

Figure 8 Structure and reaction mechanism of PBGS. (a) Crystai structure of Pseudomonas aeruginosa PBGS in compiex with the inhibitor 5-fiuoroievuiinic acid. The fundamentai structurai unit is a PBGS dimer (ieft). Four of these homodimers form the finai octameric PBGS structure (right). Each monomer (red or green) adopts the ciassicai TiM barrei foid. (b) in the proposed reaction mechanism the formation of PBG proceeds via intersubstrate C-C bond formation between C3 of the A-site ALA and C4 of the P-site ALA. This is foiiowed by C-N bond formation and reiease of the reaction product PBG.

Inhomogeneous media with micro- and nanosized structural features are known to strongly alter the character of various physical processes compared to common homogeneous materials. For example, photonic band gap (PBG) structures and metamaterials can be used for subwavelength light control [1]. Similarly, quantum heterostructures such as quantum dots and quantum wells have shown great promise in nano- and optoelectronics, as well as in quantum computing. 

The Ozin group pioneered the fabrication of planarized microphotonic structures and the growth of ordered crystals using evaporation techniques derived from convective assembly. Figure 15.17 illustrates the methods used in these experiments and some examples of PBG structures. " Opened microchannel templates were immersed vertically in a suspension of silica microspheres. The assembly was then driven by the evaporation of the colloidal suspension. Whereas the assembly of 100-500 nm... 

Figure 15.17 Illustration of the assembly mechanism leading to the growth of PBG structures (i] Opened microchannel templates are immersed vertically in a suspension of silica microspheres. Upon evaporation, channels are selectively filled with particles that self-organize into crystalline 3D structures (li). Illustration of the wave-guiding properties of such opal channels is given in (ill) through an optical micrograph and reflectance/transmittance spectra. ...

The use of photonic crystals for the enhancement of solar cells by utilizing PBG structure instead of the high-reflection Bragg mirrors has been reported by Bermel et al. [292]. They proved that a six-period triangular two-dimensional PBG structure made of air holes in silicon increases power generation more than 2 %, even more if a combination of a Bragg mirror and 2D PBG is used. A similar improvement is obtained if an eight-period inverted opal photonic crystal [293] is utilized. 

The influence of a PBG structure to the detectivity of a photonic detector may be considered in a manner analogous to that presented in Sect. 2.12. Actually a photonic crystal may be considered the ideal case of a radiative shields, describing... 

Figure 2.54 shows a photodetector enclosed within a ID PBG structure. 

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