Hard X-ray transient grating spectroscopy on bismuth germanate
© Elijah Kellum/EyeEm/Getty Images
A powerful spectroscopic technique has been extended into the X-ray region, which will enable complex materials to be analyzed at extremely high time and spatial resolutions.
Transient grating spectroscopy is an optical technique that involves using two laser pulses to generate a pattern of alternately excited and non-excited stripes in a sample and then using a third beam to measure the pattern’s evolution. It can reveal important information about how heat and charge carriers move in a material.
Higher resolutions could be obtained if X-ray were used instead of light, but it has been difficult to generate striped patterns in materials using X-rays.
Now, by exploiting a phenomenon known as the Talbot effect, a team led by researchers from the Paul Scherrer Institute in Switzerland has succeeded in performing transient grating spectroscopy using X-rays generated by an X-ray free-electron laser.
This method promises to be useful for analysing materials with atomic resolution and on femtosecond timescales.
- Nature Photonics 15, 499–503 (2021). doi: 10.1038/s41566-021-00797-9