Analysis of a silicon comb structure using an inverse Talbot-Lau neutron grating interferometer

Youngju Kim; Daeseung Kim; Daniel S Hussey; Jongyul Kim; Mona Mirzaei; Dmitry A Pushin; Charles W Clark; Seung Wook Lee

doi:10.1038/s41598-022-06409-y

Analysis of a silicon comb structure using an inverse Talbot-Lau neutron grating interferometer

Sci Rep. 2022 Mar 3;12(1):3461. doi: 10.1038/s41598-022-06409-y.

Authors

Youngju Kim^{1

2

3}, Daeseung Kim¹, Daniel S Hussey³, Jongyul Kim⁴, Mona Mirzaei^{5

6

7}, Dmitry A Pushin^{5

6}, Charles W Clark⁸, Seung Wook Lee⁹

Affiliations

¹ School of Mechanical Engineering, Pusan National University, Busan, Republic of Korea.
² Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, USA.
³ Neutron Physics Group, National Institute of Standards and Technology, Gaithersburg, MD, USA.
⁴ Neutron Science Division, Korea Atomic Energy Research Institute, Daejeon, Republic of Korea.
⁵ Institute of Quantum Computing, University of Waterloo, Waterloo, ON, Canada.
⁶ Department of Physics and Astronomy, University of Waterloo, Waterloo, ON, Canada.
⁷ Science Systems and Applications, Inc., Lanham, MD, USA.
⁸ Joint Quantum Institute, National Institute of Standards and Technology and the University of Maryland, Gaithersburg, MD, USA.
⁹ School of Mechanical Engineering, Pusan National University, Busan, Republic of Korea. seunglee@pusan.ac.kr.

Abstract

We describe an inverse Talbot-Lau neutron grating interferometer that provides an extended autocorrelation length range for quantitative dark-field imaging. To our knowledge, this is the first report of a Talbot-Lau neutron grating interferometer (nTLI) with inverse geometry. We demonstrate a range of autocorrelation lengths (ACL) starting at low tens of nanometers, which is significantly extended compared to the ranges of conventional and symmetric setups. ACLs from a minimum of 44 nm to the maximum of 3.5 μm were presented for the designed wavelength of 4.4 Å in experiments. Additionally, the inverse nTLI has neutron-absorbing gratings with an optically thick gadolinium oxysulfide (Gadox) structure, allowing it to provide a visibility of up to 52% while maintaining a large field of view of approximately 100 mm × 100 mm. We demonstrate the application of our interferometer to quantitative dark-field imaging by using diluted polystyrene particles in an aqueous solution and silicon comb structures. We obtain quantitative structural information of the sphere size and concentration of diluted polystyrene particles and the period, height, and duty cycle of the silicon comb structures. The optically thick Gadox structure of the analyzer grating also provides improved characteristics for the correction of incoherent neutron scattering in an aqueous solution compared to the symmetric nTLI.