Three Dimensional Variable-Wavelength X-Ray Bragg Coherent Diffraction Imaging

Area of Science:

• Materials Science
• Crystallography
• Imaging Techniques

Background:

• Three-dimensional (3D) Bragg x-ray coherent diffraction imaging (BCDI) is a powerful technique for nanoscale structural analysis.
• Traditional BCDI often requires sample manipulation, limiting its application in certain environments.
• In situ experiments are crucial for understanding material behavior under dynamic conditions.

Purpose of the Study:

• To present and demonstrate a novel formalism for 3D BCDI that eliminates the need for sample movement.
• To enable 3D strain imaging in complex or difficult-to-manipulate sample environments.
• To expand the applicability of in situ BCDI techniques.

Main Methods:

• Developed a 3D Fourier transform formalism accounting for x-ray wavelength variability.
• Implemented variable-wavelength BCDI by scanning the incident x-ray beam energy.
• Applied the method to invert coherent Bragg diffraction patterns from a gold nanocrystal.

Main Results:

• Successfully demonstrated 3D BCDI without sample movement using x-ray energy scanning.
• Validated the approach by reconstructing the 3D structure of a gold nanocrystal.
• The variable-wavelength method proved effective for diffraction pattern inversion.

Conclusions:

• The proposed variable-wavelength BCDI formalism offers a significant advancement for 3D imaging.
• This technique facilitates in situ 3D strain imaging in previously inaccessible experimental setups.
• It broadens the scope of materials and environments amenable to detailed structural investigation.