Superlattice optical elements

The performance of state-of-the-art Layered Synthetic Microstructures (LSM) or superlattices at x-ray energies even exceeding the soft x- ray domain is a promising sign that systems of this type may play an important role as x-ray optical elements in the energy region of interest to 6-GeV users. As will be discussed in this paper, they are particularly attractive because of their large energy bandpass compared to crystals such as Si of Ge. In fact, they have been suggested recently as elements in high throughput large bandpass x- ray monochromators tunable in the interval of 5-30 keV. For high flux applications, the hope is that LSM will prove to be stable in intense photon beams enabling them to filter out most of the heat load that will reach narrow bandpass crystal optical elements. A concurrent requirement is that their reflectivity in the x-ray region be large enough so that the gain in the bandpass will not be offset by and overall loss in flux. The effectiveness of these devices as optical elements will depend on optimization of the reflectivities of LSM through adequate design optimization modeling and fabrication techniques