Scientists have observed incredibly brief time delays in the behavior of electrons within molecules when X-rays are applied. To capture these rapid events, referred to as attoseconds, researchers utilized a laser to produce powerful X-ray bursts, enabling them to explore the internal functions of an atom.
An international research team is the first to have identified remarkably brief time delays in the activity of electrons in a molecule when subjected to X-ray exposure.
To track these fleeting high-speed occurrences, known as attoseconds, scientists used a laser to create intense X-ray flashes that facilitated the mapping of an atom’s intricate processes.
Their research showed that when X-rays eject electrons, these particles engage with another type of electron known as the Auger-Meitner electron, resulting in a secondary pause that has previously gone undetected. Lou DiMauro, one of the study’s authors and a physics professor at The Ohio State University, noted that these findings could impact various research domains, as understanding these interactions might inspire innovative ideas about complex molecular behaviors.
“X-rays serve as fascinating tools for probing matter,” DiMauro explained. “They could allow us to capture a series of detailed snapshots of a molecule as it transforms during a chemical reaction.”
This research was recently published in Nature.
Although significant advancements have been achieved in studying attosecond delays with ultraviolet light over the last twenty years, the task remained challenging due to the limited availability of sophisticated instruments required to generate them.
This difficulty led to Pierre Agostini, a professor emeritus of physics at Ohio State, receiving the 2023 Nobel Prize in Physics for his prior work in developing methods to investigate electron dynamics using light pulses lasting hundreds of attoseconds, equivalent to one quintillionth of a second.
It was only recently that advancements like the Linac Coherent Light Source (LCLS), a large free electron laser facility at Stanford University’s SLAC National Accelerator Laboratory, made the production and visualization of these pulses significantly easier, according to DiMauro.
Using the LCLS, the research team examined how electrons exist within a nitric oxide molecule, concentrating on the electrons located near the molecule’s oxygen nucleus. They discovered unexpected delays of up to 700 attoseconds, indicating that more complex factors may influence these occurrences, as mentioned by Alexandra Landsman, another co-author of the study and a physics professor at Ohio State.
“We investigated what happens when an electron is removed from deep inside an atom, and I was amazed by the complexity of dynamics involved with these tightly bound electrons,” Landsman remarked. “This suggests that the behavior is far more intricate than previously believed, necessitating improved theoretical frameworks to accurately depict light-matter interactions.”
Even though additional research is essential to deepen the understanding of these interactions, revealing previously concealed details offers scientists new perspectives to explore, according to DiMauro.
For instance, if researchers can enhance their understanding of the behavior of particles within molecules, some experts believe that their findings might play a crucial role in developing early cancer detection technologies, such as utilizing molecular markers for diagnosing blood cancers or identifying malignant tumors.
Moreover, this study suggests that researchers could leverage advancements in attosecond science, along with theoretical models, to observe matter at incredibly small scales and investigate broader mysteries of the physical universe in greater detail.
“I’m excited to see how attosecond pulses will facilitate further scientific discovery, engineering advancements, and our understanding of nature,” DiMauro stated. “The concepts presented in this paper hint at a field poised for significant growth.”
This research was funded by the U.S. Department of Energy’s Office of Science and Office of Basic Energy Sciences. James Cryan, a senior scientist at Stanford’s SLAC National Accelerator Laboratory and an alumnus of Ohio State, was the lead author of the study, with Lisa Ortmann of Ohio State also contributing as a co-author.
