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

Ehberger, Dominik; Hammer, Jakob; Eisele, Max; Krueger, Michael; Noe, Jonathan; Hoegele, Alexander; Hommelhoff, Peter

doi:10.1103/PhysRevLett.114.227601

Item

ITEM ACTIONSEXPORT

Add to Basket

Local TagsRelease HistoryDetailsSummary

Released

Journal Article

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

MPS-Authors

/persons/resource/persons60575

Hommelhoff, Peter
Hommelhoff Group, Associated Groups, Max Planck Institute for the Science of Light, Max Planck Society;

External Resource

No external resources are shared

Fulltext (restricted access)

There are currently no full texts shared for your IP range.

Fulltext (public)

There are no public fulltexts stored in PuRe

Supplementary Material (public)

There is no public supplementary material available

Citation

Ehberger, D., Hammer, J., Eisele, M., Krueger, M., Noe, J., Hoegele, A., et al. (2015). Highly Coherent Electron Beam from a Laser-Triggered Tungsten Needle Tip. PHYSICAL REVIEW LETTERS, 114(22): 227601. doi:10.1103/PhysRevLett.114.227601.

Cite as: https://hdl.handle.net/11858/00-001M-0000-002D-63B8-F

Abstract

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.