Prospects for quantitative and time-resolved double and continuous exposure off-axis electron holography

Area of Science:

• Electron microscopy
• Materials science
• Optics

Background:

• Double exposure electron holography, predating digital processing, visualized phase differences without reconstruction.
• The original method relied on superposing two off-axis electron holograms.

Purpose of the Study:

• To review and extend double exposure electron holography for quantitative, time-resolved phase shift studies.
• To adapt the technique for dynamic phenomena using external stimuli.

Main Methods:

• Describing the theory of off-axis electron hologram formation with time-dependent electron waves.
• Introducing continuous exposure electron holography for dynamic studies.
• Presenting preliminary experimental measurements.

Main Results:

• Demonstrated the extension of double exposure electron holography for time-dependent phase shifts.
• Showcased the capability to image dynamic electrostatic potentials and magnetic fields.

Conclusions:

• Continuous exposure electron holography allows quantitative analysis of oscillating phase shifts.
• The technique is applicable to high-frequency switching experiments, imaging dynamic electromagnetic fields.