Photofield electron emission from an optical fiber nanotip

Citation

Keramati, S., Passian, A., Khullar, V., & Batelaan, H. (2020). Photofield electron emission from an optical fiber nanotip. Applied Physics Letters, 117(6), 061102.

Keywords

• Photofield emission
• Nanotip electron source
• Optical fiber
• Gold coating
• Single-photon photoemission
• Low laser intensity
• Fast switching times
• Electron ghost imaging

Brief

This article presents a new type of nanotip electron source made from a gold-coated optical fiber that is tapered to a 50 nm radius, which is capable of producing fast, laser-induced electron photoemissions at low laser intensities.

Summary

This article, published in 2020 in the journal Applied Physics Letters, describes a new type of nanotip electron source. The authors, S. Keramati, A. Passian, V. Khullar, and H. Batelaan, constructed a nanotip electron source by tapering a multimode silica optical fiber to a radius of 50 nm and coating it with a thin film of gold. They observed laser-induced electron photoemission at tip bias potentials below the threshold for dark field emission and determined that the emission mechanism was single-photon photofield emission. This mechanism was chosen due to the low power regime of the CW lasers used (0.1–1 mW). The sources report that single-photon photofield emission allows for fast switching times with an upper limit on the order of 1 µs. The authors suggest that this type of electron source could be used in applications such as computational electron ghost imaging.

Origin: https://pubs.aip.org/aip/apl/article/117/6/061102/39355