Quantum-dot-array diffraction grating with single order diffraction property for soft x-ray region

Abstract

A gold transmission grating is used routinely to disperse the x-ray spectrum at the Z soft x-ray facility to measure the spectrum and temporal history of the absolute soft x-ray power emitted from z-pinch and hohlraum radiation sources. A quantum-dot-array diffraction grating (QDADG) of 250 lines/mm for soft x-ray is designed and fabricated for the first time according to the principle of binary sinusoidal transmission grating. The diffraction efficiencies of the grating are measured in the 150-300 eV photon energy range on the Beamline 3W1B of Beijing Synchrotron Radiation Facility. This article describes the basic concept and calibration techniques and presents calibration results. It is shown that the 250 lines/mm QDADG can be used to disperse light without higher-order diffractions in soft x-ray range, and the diffraction efficiencies of this grating are nearly constant (about 25%), which is beneficial in the spectrum analysis.

Single-order soft x-ray spectra with spectroscopic photon sieve*

“…In 2001, Kipp et al [8] proposed a new zone plate, or photon sieve, with a large number of pinholes distributed appropriately over the Fresnel zones that focused soft x-rays to a sharp focal spot and suppressed higher orders. Other x-ray gratings that can suppress higher-order diffractions were developed, such as the binary sinusoidal transmission grating (BSTG), [9] the quantum-dot-array diffraction grating (QDADG), [10][11][12] and the quasi-sinusoidal single-order diffraction transmission grating (QSTG). [13] Unfortunately, the BSTG and the QDADG do not have line densities greater than 1000 lines/mm.…”

A novel single-order diffraction grating: Random position rectangle grating

“…Based on the STG theory, Cao et al have proposed several types of binary sinusoidal transmission gratings [7][8][9][10][11][12][13][14][15] since 2007. All these binary sinusoidal gratings with nonharmonic diffraction are composed of lots of small size units or complicated structures.…”

“…Here, we report random position rectangle grating (RPRG) which is designed to overcome these disadvantages. The fabrication of RPRG is much easier than the binary sinusoidal gratings mentioned above [7][8][9][10][11][12][13][14][15] while the property of high-order diffraction restraint is kept. Its 1st-order theoretical absolute diffraction efficiency is as high as 4.1%, far above all binary sinusoidal transmission gratings.…”

Single order soft X-ray diffraction with quasi-random radius pinhole array spectroscopic photon sieves

“…Based on this theory, some binary single order diffraction gratings have been developed. [12][13][14][15][16][17][18][19][20][21] A quantum-dot-array diffraction grating (QDADG) has been reported by Wang et al, [12,13] and in its design a great many quantum dots are distributed on a substrate, which obey the sinusoidal function. A QDADG for visible light has been fabricated and the experiment has shown that higher-order diffractions disappear as predicted.…”