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Title: Fabrication of Nb/Pb structures through ultrashort pulsed laser deposition

Abstract

This work reports the fabrication of Nb/Pb structures with an application as photocathode devices. The use of relatively low energy densities for the ablation of Nb with ultrashort pulses favors the reduction of droplets during the growth of the film. However, the use of laser fluences in this ablation regime results in a consequent reduction in the average deposition rate. On the other hand, despite the low deposition rate, the films present a superior adherence to the substrate and an excellent coverage of the irregular substrate surface, avoiding the appearance of voids or discontinuities on the film surface. Moreover, the low energy densities used for the ablation favor the growth of nanocrystalline films with a similar crystalline structure to the bulk material. Therefore, the use of low ablation energy densities with ultrashort pulses for the deposition of the Nb thin films allows the growth of very adherent and nanocrystalline films with adequate properties for the fabrication of Nb/Pb structures to be included in superconducting radiofrequency cavities.

Authors:
; ;  [1]; ;  [2];  [3]
  1. Dipartimento di Matematica e Fisica “E. De Giorgi,” Università del Salento and Istituto Nazionale di Fisica Nucleare, 73100 Lecce (Italy)
  2. Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology-Hellas (FORTH), 100 N. Plastira St., GR 70013 Heraklion, Crete (Greece)
  3. Thin Film Physics Division, IFM, Linköping University, 581-83 Linköping (Sweden)
Publication Date:
OSTI Identifier:
22592922
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 34; Journal Issue: 4; Other Information: (c) 2016 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 42 ENGINEERING; ABLATION; CRYSTALS; DROPLETS; ENERGY BEAM DEPOSITION; ENERGY DENSITY; FABRICATION; LASER RADIATION; LASERS; NANOSTRUCTURES; PHOTOCATHODES; PULSED IRRADIATION; PULSES; RADIOWAVE RADIATION; SUBSTRATES; SURFACES; THIN FILMS

Citation Formats

Gontad, Francisco, Lorusso, Antonella, E-mail: antonella.lorusso@le.infn.it, Perrone, Alessio, Klini, Argyro, Fotakis, Costas, and Broitman, Esteban. Fabrication of Nb/Pb structures through ultrashort pulsed laser deposition. United States: N. p., 2016. Web. doi:10.1116/1.4948529.
Gontad, Francisco, Lorusso, Antonella, E-mail: antonella.lorusso@le.infn.it, Perrone, Alessio, Klini, Argyro, Fotakis, Costas, & Broitman, Esteban. Fabrication of Nb/Pb structures through ultrashort pulsed laser deposition. United States. doi:10.1116/1.4948529.
Gontad, Francisco, Lorusso, Antonella, E-mail: antonella.lorusso@le.infn.it, Perrone, Alessio, Klini, Argyro, Fotakis, Costas, and Broitman, Esteban. 2016. "Fabrication of Nb/Pb structures through ultrashort pulsed laser deposition". United States. doi:10.1116/1.4948529.
@article{osti_22592922,
title = {Fabrication of Nb/Pb structures through ultrashort pulsed laser deposition},
author = {Gontad, Francisco and Lorusso, Antonella, E-mail: antonella.lorusso@le.infn.it and Perrone, Alessio and Klini, Argyro and Fotakis, Costas and Broitman, Esteban},
abstractNote = {This work reports the fabrication of Nb/Pb structures with an application as photocathode devices. The use of relatively low energy densities for the ablation of Nb with ultrashort pulses favors the reduction of droplets during the growth of the film. However, the use of laser fluences in this ablation regime results in a consequent reduction in the average deposition rate. On the other hand, despite the low deposition rate, the films present a superior adherence to the substrate and an excellent coverage of the irregular substrate surface, avoiding the appearance of voids or discontinuities on the film surface. Moreover, the low energy densities used for the ablation favor the growth of nanocrystalline films with a similar crystalline structure to the bulk material. Therefore, the use of low ablation energy densities with ultrashort pulses for the deposition of the Nb thin films allows the growth of very adherent and nanocrystalline films with adequate properties for the fabrication of Nb/Pb structures to be included in superconducting radiofrequency cavities.},
doi = {10.1116/1.4948529},
journal = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},
number = 4,
volume = 34,
place = {United States},
year = 2016,
month = 7
}
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