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Electrochemical Etching and Characterization of Sharp Field Emission Points for Electron Impact Ionization
Published on: July 12, 2016
Strong-field above-threshold photoemission from sharp metal tips
Markus Schenk1, Michael Krüger, Peter Hommelhoff
1Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Str. 1, 85748 Garching, Germany.
Physical Review Letters
|January 15, 2011
Summary
We measured electron emission from metal tips using lasers, observing high-order above-threshold photoemission. Strong laser field effects and peak shifts indicate significant field enhancement at the tip surface.
Area of Science:
- Atomic, Molecular, and Optical Physics
- Surface Science
- Quantum Electronics
Background:
- Understanding electron emission from metal surfaces is crucial for various applications.
- Laser-driven electron emission is a key phenomenon in strong-field physics.
Purpose of the Study:
- To investigate energy-resolved electron emission from sharp metal tips.
- To explore strong-field laser effects on photoemission.
- To quantify field enhancement at nanometer scales.
Main Methods:
- Utilized a few-cycle laser oscillator to drive electron emission.
- Performed energy-resolved measurements of emitted electrons.
- Analyzed photoemission spectra at varying laser intensities.
Main Results:
- Observed above-threshold photoemission up to the 9th photon order.
- Identified suppression of the lowest order peak at ~2 × 10^11 W/cm², indicating strong-field regime onset.
- Measured a linear peak shift with intensity (-1.0 eV/(10^12 W/cm²)).
Conclusions:
- Strong-field laser effects significantly influence electron emission from sharp metal tips.
- Field enhancement at the tip surface is responsible for the observed laser field effects.
- Results provide insights into laser-matter interactions at the nanoscale.
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