Spatiotemporal Visualization of Nanoscale Rotational Dynamics by Movie-Mode Transmission Electron Microscopy

Area of Science:

• Physics
• Materials Science
• Nanotechnology

Background:

• Nanoscale rotational dynamics is crucial for applications like ultrasensitive sensing and precision manipulation.
• Observing these dynamics presents significant challenges for current techniques.

Purpose of the Study:

• To investigate the rotational dynamics of laser-excited nanotriangles at the nanosecond-nanometer scale.
• To confirm classical rigid-body rotational theory at the nanoscale.
• To quantitatively assess interfacial properties between nanotriangles and substrates.

Main Methods:

• Utilized movie-mode transmission electron microscopy for multiframe imaging.
• Achieved nanosecond and nanometer resolution for tracking rotational motion.
• Developed a motion reconstruction methodology for accurate spatiotemporal trajectory tracking.

Main Results:

• Observed distinct axis dependence in nanotriangle rotation: stable around the first principal axis, unstable around the second.
• Confirmed the tennis racket effect at the nanosecond-nanometer scale, linked to angular momentum redistribution.
• Quantitatively assessed nanotriangle-substrate adhesion using theoretical analysis of laser-induced rotation.

Conclusions:

• The tennis racket effect is confirmed at the nanosecond-nanometer scale.
• Provided an effective method for evaluating interfacial properties at the nanoscale.
• Enhanced the fundamental understanding of nanoscale rotational dynamics and rigid-body rotational theory.