Highly Coherent Electron Beam from a Laser-Triggered Tungsten Needle Tip.

Journal article

Publication Details

Author(s): Ehberger D, Hammer J, Eisele M, Krüger M, Noe J, Högele A, Hommelhoff P
Journal: Physical Review Letters
Publication year: 2015
Volume: 114
Journal issue: 22
Pages range: 227601
ISSN: 0031-9007
eISSN: 1079-7114


We report on a quantitative measurement of the spatial coherence of electrons emitted from a sharp metal needle tip. We investigate the coherence in photoemission triggered by a near-ultraviolet laser with a photon energy of 3.1 eV and compare it to dc-field emission. A carbon nanotube is brought into close proximity to the emitter tip to act as an electrostatic biprism. From the resulting electron matter wave interference fringes, we deduce an upper limit of the effective source radius both in laser-triggered and dc-field emission mode, which quantifies the spatial coherence of the emitted electron beam. We obtain (0.80±0.05) nm in laser-triggered and (0.55±0.02) nm in dc-field emission mode, revealing that the outstanding coherence properties of electron beams from needle tip field emitters are largely maintained in laser-induced emission. In addition, the relative coherence width of 0.36 of the photoemitted electron beam is the largest observed so far. The preservation of electronic coherence during emission as well as ramifications for time-resolved electron imaging techniques are discussed.

FAU Authors / FAU Editors

Ehberger, Dominik
Lehrstuhl für Laserphysik
Hammer, Jakob
Lehrstuhl für Laserphysik
Hommelhoff, Peter Prof. Dr.
Lehrstuhl für Laserphysik
Krüger, Michael
Lehrstuhl für Laserphysik

External institutions with authors

Ludwig-Maximilians-Universität (LMU)
Max-Planck-Institute of Quantum Optics (MPQ) / Max-Planck-Institut für Quantenoptik

How to cite

Ehberger, D., Hammer, J., Eisele, M., Krüger, M., Noe, J., Högele, A., & Hommelhoff, P. (2015). Highly Coherent Electron Beam from a Laser-Triggered Tungsten Needle Tip. Physical Review Letters, 114(22), 227601. https://dx.doi.org/10.1103/PhysRevLett.114.227601

Ehberger, Dominik, et al. "Highly Coherent Electron Beam from a Laser-Triggered Tungsten Needle Tip." Physical Review Letters 114.22 (2015): 227601.


Last updated on 2019-09-09 at 14:03