Supermirrors are multilayer structures where the thickness of the layers down through the structure changes so that wide-band reflection occurs. The principles were developed in the mid-70s and have been used extensively for neutron optics. Absorption in the upper layers limits the attainable reflectivity for x rays. For hard x rays (≥ 15 keV), the absorption, however, is low enough that it is possible to design supermirrors with 10 - 70% reflectivity in a band ≈ 3 times the width of the total reflection regime. Supermirrors of W/Si and Ni/C have been successfully fabricated and characterized. The measured x-ray reflectivities are well accounted for by the standard dynamical theories of multilayer reflection. Hard x ray applications that could benefit from x-ray supermirror coatings include focusing and imaging instrumentation for astrophysics, collimating and focusing devices for synchrotron radiation, and particle filtering in plasma diagnostics.
|Journal||Proceedings of S P I E - International Society for Optical Engineering|
|Publication status||Published - 1994|
|Event||SPIE 1994 International Symposium on Optics, Imaging, and Instrumentation: X-Ray and Ultraviolet Spectroscopy and Polarimetry - San Diego, United States|
Duration: 24 Jul 1994 → 29 Jul 1994
|Conference||SPIE 1994 International Symposium on Optics, Imaging, and Instrumentation|
|Period||24/07/1994 → 29/07/1994|
|Other||SPIE vol. 2283|
- Imaging techniques
- Optical coatings
- Structure (composition)
- X ray spectroscopy
Joensen, K. D., Gorenstein, P., Christensen, F. E., Hoghoj, P., Ziegler, E., Susini, J., Freund, A. K., Siddons, D. P., & Wood, J. L. (1994). Prospects for supermirrors in hard x-ray spectroscopy. Proceedings of S P I E - International Society for Optical Engineering, 2283, 130-141.