Tailoring Superconductivity with Quantum Dislocations
Name
Dislon_Final_V2.pdf
Size
267.29 KB
Format
Adobe PDF
Checksum (MD5)
d25b7d271beece9f26e4e06b4abe30e8
Author(s)
Mahan, Gerald D.
Li, Mingda
Song, Qichen
Liu, Te Huan
Dresselhaus, Mildred
Chen, Gang
Date Issued
July 2017
Journal
Nano Letters
Publisher
American Chemical Society (ACS)
Citation
Li, Mingda et al. “Tailoring Superconductivity with Quantum Dislocations.” Nano Letters 17, 8 (July 2017): 4604–4610 © 2017 American Chemical Society
Version
Author's final manuscript
Abstract
Despite the established knowledge that crystal dislocations can affect a material’s superconducting properties, the exact mechanism of the electron-dislocation interaction in a dislocated superconductor has long been missing. Being a type of defect, dislocations are expected to decrease a material’s superconducting transition temperature (T[subscript c]) by breaking the coherence. Yet experimentally, even in isotropic type I superconductors, dislocations can either decrease, increase, or have little influence on T[subscript c]. These experimental findings have yet to be understood. Although the anisotropic pairing in dirty superconductors has explained impurity-induced T[subscript c] reduction, no quantitative agreement has been reached in the case a dislocation given its complexity. In this study, by generalizing the one-dimensional quantized dislocation field to three dimensions, we reveal that there are indeed two distinct types of electron-dislocation interactions. Besides the usual electron-dislocation potential scattering, there is another interaction driving an effective attraction between electrons that is caused by dislons, which are quantized modes of a dislocation. The role of dislocations to superconductivity is thus clarified as the competition between the classical and quantum effects, showing excellent agreement with existing experimental data. In particular, the existence of both classical and quantum effects provides a plausible explanation for the illusive origin of dislocation-induced superconductivity in semiconducting PbS/PbTe superlattice nanostructures. A quantitative criterion has been derived, in which a dislocated superconductor with low elastic moduli and small electron effective mass and in a confined environment is inclined to enhance T[subscript c]. This provides a new pathway for engineering a material’s superconducting properties by using dislocations as an additional degree of freedom.
Keywords: Dislocations; disordered superconductor; effective field theory; electron-dislocation interaction
MIT Department
Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science
Massachusetts Institute of Technology. Department of Mechanical Engineering
Massachusetts Institute of Technology. Department of Nuclear Science and Engineering
Massachusetts Institute of Technology. Department of Physics
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1021/acs.nanolett.7b00977
