Defective layers

One period of such a structure can be considered as a finite periodic grating with a defect layer in its middle and that is why a very narrow resonance (defect mode) appears inside of the band gap. 

In addition, the composition of the layers AX and BX2 may vary, i.e., some or all of the atoms X may be missing. Layers of this sort may be called "defective" and they have compositions A and BX (the case of a layer of composition B is identical to A). All possible meshes of full or defective layers of type AX and BX2 are illustrated in Figure 2. 

Another method presented in this paper is the indirect eb method when the C -lace of a LiNbOs ferroelectric is preliminary coated by a highly defective layer of the amorphous photo-resist material pmma. The thickness of this dielectric layer is large enough to protect the LiNb03 from penetration of high energy electrons into the bulk. In the presented calculations and simulation a very limited number of electrons penetrated into the LiNbOs crystal, so most of the injected electron charge remains trapped in the pmma layer. 

Removing of defective layers from the surface of shaped parts is an important... 

The decomposition of magnesium hydroxide has been evaluated as a process of nucleation and growth of MgO crystals within the brucite matrix. The formation of a defect layer of hydroxide structure, which suddenly recrystallizes to the cubic MgO structure when the fracture stress is exceeded in the defect layer, has been postulated (Freund et al., 1975 Guilliat et al., 1970 Garn et al., 1978 Lpnvik, 1978). The MgO crystals formed have an expanded cubic lattice that upon increasing calcination temperature gradually decreases in size until the equilibrium unit cell dimension is reached. 

In crystal form II the (100) layers are stacked on top of each otherThe overall morphology of PPT fibers has been described as practically fully crystalline, but with periodic defect layers and 5° pleating of the fibrils making up the macrofiber. Etching experiments yield 35 nm long single crystal grains, but with continued correlation of the stiff chains across defect layers to about 80 nm... 

The second defect layer is located at a significant depth, and the dislocation loops do not influence the optical and structural quality of the crystallites. 

Figure 33 (a) HREM image of a defect where the two rows of lead atoms, which appear as double white rows in the thick part of the crystal (white arrows), disappeared they are replaced by three rows of staggered dots, (b) Drawing of the ide ized structural model the defect would consists of the local replacement of a "PbO-( -PbO" triple layer by a "CUO2-Y-Q1O2" triple layer. The defective layer is marked by a black arrow. 

Kosmidou EP, Kriezis EE, Tsiboukis TD (2005) FDTD analysis of photonic crystal defect layers filled with liquid crystals. Opt Quantum Electron 37(1) 149-160... 

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