English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Some topological insulators become superconducting when doped with Cu and Pd.Superconductivity in a non-superconductor may be induced by proximity effect:i.e. Contacting a non-superconductor with a superconductor. The superconductingmacroscopic wave function will induce electronic pairing into the normalcompound. In the simplest topological insulator, Bi$_2$Se$_3$,superconductivity may be induced with Pb. We studied with point contactjunctions formed by contacting Bi$_2$Se$_3$ crystals and Pb, glued and pressedwith silver paste and/or applying low heat to the Pb to improve the contact.Junctions were formed with a thin tungsten plated gold W(Au) wire as oneelectrode, and the other $Bi_2Se_3$ and Pb. We study the characteristics of theelectron coupling; the transition temperature,$T_C$, evolution with temperatureof the energy gap, $\Delta$, and 2$\Delta$/K$_B$T$_C$ ratio. The superconductorBi$_2$Se$_3$-Pb behaves different as explained in the classical BCS theory. InBCS a superconductor is only weak or strong coupled, depending on theelectronic interaction that form the electronic condensate. Thisdifferentiation is given by the size of the mentioned ratio. BCS Typical valuesare 3.53 to about 4.3 for weak or strong coupling limits respectively. In thisstudy performed in Bi$_2$Se$_3$-Pb we found different values to the normal onesfrom 10 to 23, indicating very strong limit. Those values never have beenobserved in other superconductor. The transition temperatures found varies from2.7 to 7 K. This information and other results will be presented in this paper.

Pb induces superconductivity in Bi2Se3 analyzed by point contact spectroscopy