High-extinction electron pulses by laser-triggered emission from a Schottky emitter

Abstract

We study electron emission from a Schottky tip induced by nanosecond laser pulses. Prompt sub-nanosecond emission is observed at low laser power, with moderate voltage bias applied to the tip. We show that electron pulses demonstrate high extinction with electron emission after the pulse suppressed by up to 92 dB. Photoemission is shown to be highly nonlinear with laser intensity while maintaining nearly linear field emission, as probed by the laser polarization dependence. We suggest the emission is described by a photo-assisted thermally enhanced field emission process.

RF pulse shaping for gated electron mirrors

“…Although we have successfully used the method in conjunction with active scope probes to directly probe the gated mirror electrode, our ultimate goal is to implement this in situ with a complete MPTEM. We are optimistic that timeand energy-resolved measurements of both transmitted and reflected electrons will allow us to close the feedback loop [13]. We have identified several candidate commercial RF amplifiers with the requisite power and bandwidth, and we are confident such a setup will work to drive the gated mirror at the required voltage.…”