The paper primarily exploits the use of the SEM as an accelerator in a physics lab. Access to a traditional accelerator is limited to a few number of universities and comparatively, SEMs can be found more commonly. A SEM can be used as a low scaled single-ended accelerator with accelerating potentials ranging from 50kV - 3MV (30kV most common).
The idea of using the SEM as an accelerator is that a beam electrons/particles are accelerated through beam-shaping magnets to hit a beam-target. A Faraday cup can be used to measure the current that the beam receives.
[Faraday Cup: a metal (conductive) cup designed to catch charged particles in vacuum to determine the number of ions or electrons hitting the cup.
https://en.wikipedia.org/wiki/Faraday_cup]
Condenser Lens 1/Condenser Lens 2 - Field/Condenser Magnets
Condenser Lens 3 - Objective Lens
Certain controls of the SEM can be relabelled to help physics students to relate a SEM to an accelerator system. Such as,
SEM ------------> Accelerator
Contrast & Brightness Detector Range & Gain
Magnification (MAG) Scanning Magnet Control
FOCUS Objective Magnet Control
SPOT SIZE Condenser Magnet Control
The magnetic focusing has an observable effect that is the change in direction (angle of rotation) due to the changing magnetic field. The image of the SEM can be seen to rotate from the expected position (spiral motion) that can be predicted from -ev X B of the objective lens (lens 3)
A suitable application that the SEM can be used for in physics lab is to measure the deBroglie wavelength from the diffraction aperture in the SEM. The experimental physics work that can be done using SEM is accelerator physics, atomic physics, and electron-solid interactions.
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