Dissertation/Thesis Abstract

Fabrication of Josephson junctions by nanosphere lithography
by Arias, Gilbert, M.S., California State University, Long Beach, 2016, 59; 10147318
Abstract (Summary)

The proximity effect allows the Cooper pairs of superconductors to tunnel into non-superconducting materials. Cooper pairs in the triplet state with their spins parallel have a large penetration length through an inhomogeneous ferromagnetic barrier. This long-range odd triplet component can be measured directly using Josephson junctions. We successfully developed the multi-step fabrication procedure of nanopillar Josephson junctions using nanosphere lithography. Charged polystyrene spheres with various diameters were tested and the 800 nm spheres gave the best result. Based on the statistics of the adsorbed spheres, we predicted that about 20 to 80 nanopillars were fabricated between the top and the bottom Nb electrodes. Possibly due to this complicated structure, transport measurements did not show evidence of long-range odd triplet component. Future work should focus on reducing the size of electrodes to conduct the transport measurement on only a few or a single nanopillar Josephson junctions.

Indexing (document details)
Advisor: Gu, Jiyeong
Commitee: Bill, Andreas, Gredig, Thomas
School: California State University, Long Beach
Department: Physics and Astronomy
School Location: United States -- California
Source: MAI 56/01M(E), Masters Abstracts International
Subjects: Nanoscience, Physics, Condensed matter physics
Publication Number: 10147318
ISBN: 978-1-369-02543-9
Copyright © 2021 ProQuest LLC. All rights reserved. Terms and Conditions Privacy Policy Cookie Policy