Ultrafast oscilloscope based on laser-triggered field emitters.

Area of Science:

• Physics
• Materials Science
• Electron Optics

Background:

• Laser-triggered electron emission from sharp metal tips offers a novel approach for generating high-brightness, ultrafast electron beams.
• Potential applications include advanced electron microscopy, particle acceleration, and electron interferometry.

Purpose of the Study:

• To demonstrate the capability of laser-triggered electron emission for sampling instantaneous radio frequency (RF) voltages.
• To validate the technique by mapping an RF signal with high temporal resolution.

Main Methods:

• Utilized a sharp metal tip as a field emitter.
• Employed laser pulses to trigger electron emission.
• Applied a 9.28 GHz RF signal derived from the laser's repetition rate to the field emitter.
• Achieved temporal mapping in 22.4 femtosecond (fs) steps.

Main Results:

• Successfully demonstrated laser-triggered electron emission as a viable ultrafast electron source.
• Achieved precise mapping of the 9.28 GHz RF signal with an accuracy of 28 millivolts (mV).
• Validated the ultrafast sampling capability of the electron emission process.

Conclusions:

• Laser-triggered electron emission is a promising technique for high-resolution temporal measurements of RF fields.
• This method enables advanced applications requiring ultrafast electron beams and precise voltage sampling.