Anomalous Photon-Induced Near-Field Electron Microscopy.

Area of Science:

• Quantum optics
• Electron microscopy
• Particle physics

Background:

• Free electron interaction with radiation is fundamental across various sources like Smith-Purcell radiation.
• Understanding these interactions is key for advancements in dielectric laser accelerators and photo-induced near-field electron microscopy (PINEM).

Purpose of the Study:

• To distinguish and characterize classical and quantum regimes of free electron-radiation interaction.
• To introduce a novel anomalous PINEM (APINEM) regime and explore its properties.
• To investigate the particle-wave duality in electron-light interactions.

Main Methods:

• Modeling electrons as coherent quantum wave packets with specific initial conditions.
• Analyzing the topology of electron wave packets in phase space.
• Investigating quantum interference beats within the APINEM regime.

Main Results:

• Identified three distinct interaction regimes: point-particle-like acceleration, quantum wave function (PINEM), and anomalous PINEM (APINEM).
• Demonstrated that APINEM exhibits quantum interference beats.
• Showcased APINEM's potential to improve spectral resolution in postselective electron microscopy.

Conclusions:

• The phase space topology of quantum electron wave packets universally distinguishes interaction regimes.
• APINEM represents a new regime with potential applications in advanced electron microscopy.
• The transition between regimes highlights the history-dependent nature of quantum electron-light interactions.