Current characterization methods fall short on multiple fronts. Far-field optical techniques are constrained by the diffraction limit, restricting spatial resolution to above 100 nm, while conventional electron microscopy delivers high spatial detail but at video-rate or slower speeds, losing ultrafast temporal information. Time-resolved spectroscopies often sacrifice spatial specificity, and energy-filtered imaging rarely synchronizes with femtosecond excitation. Moreover, many setups lack in situ control of sample environment, electrical biasing, or temperature, preventing realistic studies under operating conditions. Consequently, researchers face a trade-off between spatial precision, temporal fidelity, and environmental relevance.
Description
By combining ultrafast laser excitation with photoelectron imaging microscopy the inventors have developed a 4 dimensional imaging technique for studying the time evolution of surface electromagnetic fields and excited electron distributions with 10 fs temporal, <50 nm spatial, and <0.1 eV energy resolution. This invention is a product and process for imaging electromagnetic fields in nanostructures.
Applications
Semiconductor defect detection
Photonic device quality control
Plasmonic sensor optimization
Microelectronics failure analysis
Ultrafast carrier dynamics imaging
Advantages
Four-dimensional (x, y, time, energy) imaging of electromagnetic fields at material surfaces
Sub-50 nm spatial resolution combined with femtosecond-scale (sub-5 fs) temporal resolution
Interferometric delay control with sub-50 attosecond accuracy for sub-optical-cycle measurements
Energy- and momentum-resolved photoelectron detection for detailed carrier relaxation studies
In situ sample preparation and environmental control (temperature, electric/magnetic fields, bias) in ultrahigh vacuum
Integration with atomistic and effective‐mass simulations for correlative analysis
IP Status
https://patents.google.com/patent/US8085406B2
