Bragg mirrors

Bradyrhizobium Bragg effects Bragg equation Braggite Bragg mirrors Bragg reflector Bragg s law Braids Brain... 

Bragg mirrors on periodic stacks of layers Periodic stacks of metal nanoparticles or dielectric layers with alternating high and low refractive index produce a desired reflectance of the mirror that depends on the thickness and the refractive index of the layers in the stack 16,17... 

Snow, P. A. Squire, E. K. Russell, P. S. J. Canham, L. T., Vapor sensing using the optical properties of porous silicon bragg mirrors, J. Appl. Phys. 1999, 86, 1781 1784... 

Vertical emission can also be achieved by the application of dielectric Bragg mirrors layers, which is in principle the DBR structure applied to the direction of the him normal. Such microcavities have been shown to alter the (electroluminescence spectrum of devices as well as the angular radiation characteristics [200-204], Normally, the angular dependence of the emission from a thin him follows Lambert s law [205]. 

Further improvement of the structural and optical properties of the PLD Bragg mirrors was achieved by substituting ZnO by yttria stabilized zir-conia (YSZ, with typically 9 at. % Y2O3), as demonstrated in Fig. 7.29. A considerable increase of the maximum reflectivity of the Bragg structures from about 90-99% was realized by doubling the number of YSZ-MgO layer pairs from 5.5 to 10.5 as shown in Fig. 7.29 (top). The experimentally obtained single layer thicknesses of the 5.5 and 10.5 pair structure are given in the caption and show smaller variation compared to the MgO-ZnO structure of Fig. 7.28. Indeed, the SNMS isotope intensity depth profile... 

Fig. 7.28. SNMS isotope intensity depth profile of a 9.5 pair ZnO-MgO Bragg mirror grown by PLD on c-plane sapphire. This particular Bragg structure had a maximum reflectivity of 85% at 2.3 eV photon energy [94], The single layer thicknesses obtained from UV-vis ellipsometry varied from 80-96 nm (MgO) and 41-71 nm (ZnO)...

Fig. 7.29. Top Reflectivity at normal incidence of two PLD grown Bragg mirrors with 5.5 and 10.5 YSZ-MgO layer pairs obtained from the ellipsometry model analysis. By doubling the layer number, the reflectivity was increased from 90 to 99%. The UV-vis ellipsometry data were fitted best with layer thicknesses of 38-46 nm YSZ/48-54nm MgO for the 5.5 layer pair Bragg, and 46.4 0.7 nm YSZ and 51.9 0.5 nm MgO for the 10.5 pair Bragg. Measured and calculated by R. Schmidt-Grand. Bottom SNMS isotope intensity depth profile of this 5.5 x YSZ/MgO Bragg structure...

Doublets of folded longitudinal acoustic (LA) phonons due to the superlattice periodicity [143] can also be seen in the Raman spectra of the SLs (indicated by arrows in Fig. 21.2). The positions of the doubled peaks agree well with the first doublet frequencies calculated within the elastic continuum model [144]. The observation of the LA phonon folding suggests that these superlattices possess the requisite structural quality for acoustic Bragg mirrors and cavities to be used for potential coherent phonon generation applications [145-147]. 

Fig. 6.32 Chirped mirrors (a) Bragg mirror with no chirp (b) simple chirped mirror for one wavelength (c) double-chirped mirror with matching sections to avoid residual reflections [695]...

Bottom reflector i d i (AiAs/AIGaAs Bragg mirror)... 

Fig. 6.35 Semiconductor Bragg mirror with a 15 nm saturable absorber layer of GaAs [694]...

Calvo, M. E. Miguez, H., Flexible, Adhesive, and Biocompatible Bragg Mirrors Based on Polydimethylsiloxane Infuilitrated Nanoparticle Multilayers. Chem. Mater. 2010, 22, 3909-3915. 

Ivanov I, Skryshevsky VA, Nychyporuk T, Lemiti M, Makarov AV, Klyui NI, Tretyak OV (2013) Porous silicon Bragg mirrors on single- and multi-crystalline silicon for solar cells. Renew Energy 55 79-84... 

Gargas DJ, Muresan O, Sirbuly DJ, Buratto SK (2006) Micropattemed porous-silicon Bragg mirrors by dry-removal soft lithography. Adv Mater 18(23) 3164 Golub MA, Hutter T, Ruschin S (2010) Diffractive optical elements with porous silicon layers. Appl Opt 49(8) 1341-1349... 

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