Bragg Reflector Mirrors and ZnO Quantum Well Structures

2 Bragg Reflector Mirrors and ZnO Quantum Well Structures 

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 

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