X-ray Studies Reveal Dynamics of Buckyball Under Laser Fields

Researchers at the Max Planck Institute for Nuclear Physics in Heidelberg and the Max Planck Institute for the Physics of Complex Systems in Dresden, along with collaborators from the Max Born Institute in Berlin and groups in Switzerland, the USA, and Japan, have conducted groundbreaking studies on the behavior of the Buckminsterfullerene molecule, or C60, when exposed to intense laser fields.

This work, conducted at the Linac Coherent Light Source at the SLAC National Accelerator Laboratory, utilized ultrashort, high-power X-ray pulses generated by accelerator-based free electron lasers to directly observe the dynamics of C60.

The findings, which were reported in Science Daily, show how strong laser fields can reshape molecular structures and guide chemical reactions through the manipulation of atomic movements. The research team analyzed X-ray diffraction patterns to extract two critical parameters: the average radius of the molecule and the Guinier amplitude, which indicates the strength of the X-ray scattering signal.

The studies revealed that at low laser intensities, C60 initially expands before fragmentation occurs, marked by a gradual decrease in the Guinier amplitude. As intensity increases, the molecule undergoes a rapid expansion followed by a dramatic drop in amplitude, indicating that most outer valence electrons are expelled almost instantaneously.

This rapid electron loss suggests that the molecule experiences a violent interaction, described as a 'kick' from the laser field. The theoretical models used to simulate these interactions initially captured only part of the experimental behavior, including oscillations in the radius and amplitude.

However, these oscillations were absent in the actual data. By incorporating an ultrafast heating mechanism that affects atomic positions into their models, the researchers achieved a better alignment with experimental results.

This highlights the need for ongoing experimental and theoretical work to fully understand the dynamics of molecular responses to intense laser fields. The study emphasizes the importance of X-ray movies in exploring fundamental quantum processes in complex molecules, ultimately supporting long-term efforts to control chemical reactions with precisely shaped laser fields.

Such advancements are crucial for the field of molecular physics and quantum mechanics, paving the way for new applications in science and technology.