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Transmission characteristics are studied for hybrid structures combining defects and multiple heterostructures. It is shown that the nontransmission frequency range can be substantially enlarged and the phenomenon of multiple-channeled filtering can be realized by adjusting the number, position, and size of the defects. One, two, and three channeled filters are considered in the structures. Examples are studied theoretically by transfer matrix methods.

A remarkable magnetostriction λ111 as large as 6700 ppm was found at 70 K in PrFe1.9 alloy. This value is even larger than the theoretical maximum of 5600 ppm estimated by the Steven's equivalent operator method. The temperature dependence of λ111 for PrFe1.9 and TbFe2 alloys follows well with the single-ion theory rule, which yields giant estimated λ111 values of about 8000 and 4200 ppm for PrFe1.9 and TbFe2 alloys, respectively, at 0 K. The easy magnetization direction of PrFe1.9 changes from [111] to [100] as temperature decreases, which leads to the abnormal decrease of the magnetostriction λ. The rare earth sublattice moment increases sharply in PrFe1.9 alloy with decreasing temperature, resulting in the remarkably largest estimated value of λ111 at 0 K according to the single-ion theory.

Nonperiodic molybdenum/silicon broadband multilayer polarizers have been designed using numerical optimization algorithm and fabricated using direct current magnetron sputtering. Their performances have been characterized using the high precision eight-axis soft x-ray polarimeter at the BESSY facility. Different multilayers have measured s-polarized reflectivities of 27% at 13.1nm and higher than 15% over the wavelength range of 13–19nm. Nearly constant s reflectivity, up to 37%, is observed over the 15–17nm wavelength range, where the degree of polarization is more than 98%. Furthermore, these multilayer polarizers also show high s reflectivity and polarization over a broad angular range at fixed wavelength.