Abstract

Numerical and experimental studies have been performed to evaluate the enhancement of diffraction efficiency of diffraction gratings around B $K$-emission by overcoating lanthanum series layers on conventional metal-coated laminar-type gratings. We propose an optical design method based on the concept of spectral flux given by collection efficiency and diffraction efficiency. A diffraction grating with a small angle of incidence provides an advantage to soft x-ray spectrographs because it collects the emission at a larger solid angle compared to that of conventional grazing incidence diffraction gratings. Numerical calculations indicated that La and ${\rm{La}}{{\rm{F}}_3}$ were promising as overcoating materials on a laminar-type Ni-coated diffraction grating, and we performed an experimental study using ${\rm{La}}{{\rm{F}}_3}$ and La/C overcoatings, considering their producibility and durability. The diffraction efficiencies were measured using a reflectometer at a synchrotron facility. The diffraction efficiencies observed at 183.4 eV were 29.4% and 34.3% at angles of incidence of 85.1° and 84.9° for ${\rm{Ni}}/{\rm{La}}{{\rm{F}}_3}$ and Ni/La/C gratings, respectively.

© 2021 Optical Society of America

Development of multilayer laminar-type diffraction gratings to achieve high diffraction efficiencies in the 1-8 keV energy region

Masahiko Ishino, Philip A. Heimann, Hiroyuki Sasai, Masatoshi Hatayama, Hisataka Takenaka, Kazuo Sano, Eric M. Gullikson, and Masato Koike
Appl. Opt. 45(26) 6741-6745 (2006)

Fabrication and evaluation of a wideband multilayer laminar-type holographic grating for use with a soft-x-ray flat-field spectrograph in the region of 1.7 keV

Takashi Imazono, Masahiko Ishino, Masato Koike, Hiroyuki Sasai, and Kazuo Sano
Appl. Opt. 46(28) 7054-7060 (2007)

Efficiency and polarization performance of a multilayer-coated laminar grating in the 6.5–6.9-nm wavelength region

Sadayuki Ishikawa, Takashi Imazono, Tadashi Hatano, Mihiro Yanagihara, and Makoto Watanabe
Appl. Opt. 41(4) 763-767 (2002)

Multilayer-coated laminar grating with 16% normal-incidence efficiency in the 150-Å wavelength region

J. F. Seely, M. P. Kowalski, R. G. Cruddace, K. F. Heidemann, U. Heinzmann, U. Kleineberg, K. Osterried, D. Menke, J. C. Rife, and W. R. Hunter
Appl. Opt. 36(31) 8206-8213 (1997)

Laminar and blazed type holographic gratings for a versatile soft x-ray spectrograph attached to an electron microscope and their evaluation in the 50–200 eV range

Takashi Imazono, Masato Koike, Tetsuya Kawachi, Noboru Hasegawa, Masaru Koeda, Tetsuya Nagano, Hiroyuki Sasai, Yuki Oue, Zeno Yonezawa, Satoshi Kuramoto, Masami Terauchi, Hideyuki Takahashi, Nobuo Handa, Takanori Murano, and Kazuo Sano
Appl. Opt. 51(13) 2351-2360 (2012)