English

Imaging and controlling electron motion and chemical structural dynamics of biological system in real time and space

Chemical Physics 2025-10-03 v1 Atomic and Molecular Clusters Biological Physics

Abstract

Ultrafast electron microscopy (UEM) has found widespread applications in physics, chemistry, and materials science, enabling real-space imaging of dynamics on ultrafast timescales. Recent advances have pushed the temporal resolution of UEM into the attosecond regime, enabling the attomicroscopy technique to directly visualize electron motion. In this work, we extend the capabilities of this powerful imaging tool to investigate ultrafast electron dynamics in a biological system by imaging and controlling light induced electronic and chemical changes in the conductive network of multicellular cable bacteria. Using electron energy loss spectroscopy (EELS), we first observed a laser induced increase in {\pi}-electron density, accompanied by spectral peak broadening and a blueshift features indicative of enhanced conductivity and structural modification. We also traced the effect of ultrafast laser pumping on bulk plasmon electron oscillations by monitoring changes in the plasmon like resonance peak. Additionally, we visualized laser induced chemical structural changes in cable bacteria in real space. The imaging results revealed carbon enrichment alongside a depletion of nitrogen and oxygen, highlighting the controllability of chemical dynamics. Moreover, time resolved EELS measurements further revealed a picosecond scale decay and recovery of both {\pi}-electron and plasmonic features, attributed to electron phonon coupling. In addition to shedding light on the mechanism of electron motion in cable bacteria, these findings demonstrate ultrafast modulation and switching of conductivity, underscoring their potential as bio-optoelectronic components operating on ultrafast timescales.

Keywords

Cite

@article{arxiv.2510.02105,
  title  = {Imaging and controlling electron motion and chemical structural dynamics of biological system in real time and space},
  author = {Ligong Zhao and Mohamed Sennary and Dina Hussein and Anaisa Coelho and Tingting Yang and Mohamed Y. El-Naggar and Mohammed Th. Hassan},
  journal= {arXiv preprint arXiv:2510.02105},
  year   = {2025}
}

Comments

18 pages, 5 figures