YB sub 66 as a new soft x-ray monochromator for synchrotron radiation (abstract)

Journal Article · Wed Jan 01 04:00:00 EST 1992 · Review of Scientific Instruments; (United States)

DOI:https://doi.org/10.1063/1.1143058· OSTI ID:5645525

Rek, Z; Wong, J; Tanaka, T; Shimkaveg, G; Eckart, M ^[1]

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1. Lawrence Livermore National Laboratory, University of California, P.O. Box 808, Livermore, California 94551 (United States)

YB{sub 66}, a complex binary semiconducting compound with a cubic crystal structure and a lattice parameter of 23.44 A, is potentially a very good candidate for monochromatization of soft x-ray synchrotron radiation. The features such as: a large interatomic spacing, lack of absorption edges by the constituent elements in the region 1--2 keV, very narrow intrinsic rocking curves for (400) and (222) reflections and good thermal and mechanical properties make the material very useful. Using the known structure factors for the (400) and (222) reflections, having 2{ital d} values of 11.76 and 13.53 A, respectively, their rocking curves have been calculated and are shown (J. Wang, G. Shimkaveg, W. Goldstein, M. Eckart, T. Tanaka, Z. Rek, H. Tompkins, Nucl. Instrum. Methods A {bold 291}, 243 (1990)) to be comparable to or better than that of beryl (10{bar 1}0). A novel indirect heating floating zone method for growing large size crystals was used by Tanaka and his coworkers in Japan (T. Tanaka, S. Otani, and Y. Ishizawa, J. Cryst. Growth {bold 73}, 31 (1985)). Numerous modifications of this technique and double-zone passes were applied to reduce sub grain structure and lattice deformations. The crystalline perfection and absence of defects is critical to obtaining high energy resolution and good crystal reflectivity. Crystals large enough to accept 1 mrad of radiation, with growth direction (100) and (110) were grown. Rocking curve measurements, etch pit density, and x-ray white beam topography are used to characterize the quality of these crystals as a function of some critical growth parameters. Most crystals exhibit the existence of sub grain boundaries. Areas perfect enough were observed to give {similar to} 0.5 eV energy resolution. Recent experiments in crystal growth, results of crystals characterization, and comparison with theoretical calculations will be discussed.

• OSTI ID: 5645525
• Journal Information: Review of Scientific Instruments; (United States), Journal Name: Review of Scientific Instruments; (United States) Vol. 63:1; ISSN RSINA; ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

440101* -- Radiation Instrumentation-- General Detectors or Monitors & Radiometric Instruments
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
BORIDES
BORON COMPOUNDS
BREMSSTRAHLUNG
CRYSTAL GROWTH
ELECTROMAGNETIC RADIATION
EQUIPMENT
IONIZING RADIATIONS
MATERIALS
MONOCHROMATORS
RADIATIONS
SEMICONDUCTOR MATERIALS
SOFT X RADIATION
SYNCHROTRON RADIATION
TRANSITION ELEMENT COMPOUNDS
X RADIATION
X-RAY EQUIPMENT
YTTRIUM BORIDES
YTTRIUM COMPOUNDS