Ferromagnet–superconductor nanocontacts grown by focused electron/ion beam techniques for current-in-plane Andreev Reflection measurements

• Published in: Solid state communications Vol. 151; no. 1; pp. 37 - 41
• Main Authors: Sangiao, S., Morellón, L., Ibarra, M.R., De Teresa, J.M.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 2011; Elsevier
• Subjects: A. Heterojunctions; A. Superconductors; B. Nanofabrication; Condensed matter: electronic structure, electrical, magnetic, and optical properties; D. Electronic transport; Deposition; Electronics; Exact sciences and technology; Ion beams; Mesoscopic and nanoscale systems; Nanocomposites; Nanomaterials; Nanostructure; Physics; Proximity effects, weak links, tunneling phenomena, and josephson effects, adreev effect, sn and sns junctions; Reflection; Superconducting films and low-dimensional structures; Superconductivity; A. Heterojunctions; B. Nanofabrication; A. Superconductors; D. Electronic transport; Andreev reflection; Electrical conductivity; Superconducting energy gap; Ferromagnetic materials; Spin polarization; Focused electron beam technology; Cobalt; Focused ion beam technology; Superconductors; Transition elements; Tungsten; Nanocontacts; Transport processes; IV characteristic; Heterostructures
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/j.ssc.2010.10.028

Superconductor-ferromagnetic in-plane nanocontacts have been created with focused-electron/ion-beam-induced deposition techniques for studies of Andreev Reflection. The final resistance of the nanocontact is tuned during the growth by in situ resistance measurements. The results show that Co nanodeposits grown with focused electron beam have large spin polarization (∼35%), making this nanomaterial of great potential for use in Spin Electronics applications. The experiments have also allowed the determination of the superconducting gap of the W-based nanodeposits grown with focused ion beam.
► Ferromagnetic-superconductor nanocontacts created with focused electron/ion beams. ► The conductance curves can be fitted using BTK model including spin polarization. ► The spin polarization of the FEBID-Co nanodeposit obtained from fits is about 35%. ► The FIBID-W is a stable superconductor showing good BCS behaviour at the nanoscale.