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arXiv · 1009.2872

Strong-field above-threshold photoemission from sharp metal tips

Markus Schenk·Michael Krüger·Peter Hommelhoff
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Abstract

We present energy-resolved measurements of electron emission from sharp metal tips driven with low energy pulses from a few-cycle laser oscillator. We observe above-threshold photoemission with a photon order of up to 9. At a laser intensity of 2*10^11 W/cm^2 suppression of the lowest order peak occurs, indicating the onset of strong-field effects. We also observe peak shifting linearly with intensity with a slope of around -1.8eV / (10^12 W/cm^2). We attribute the magnitude of the laser field effects to field enhancement taking place at the tip's surface.

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Markus Schenk, Michael Krüger, Peter Hommelhoff. 2010-09-15. Strong-field above-threshold photoemission from sharp metal tips. https://doi.org/10.1103/physrevlett.105.257601

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