Evidence of unconventional superconductivity on the surface of the nodal semimetal CaAg1−xPdxP
Surface states of topological materials provide extreme electronic states for unconventional superconducting states. CaAg 1− x Pd x P is an ideal candidate for a nodal-line Dirac semimetal with drumhead surface states and no additional bulk bands. Here, we report that CaAg 1− x Pd x P has surface st...
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Published in | Nature communications Vol. 14; no. 1; p. 6817 |
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Main Authors | , , , , , , , , , |
Format | Journal Article |
Language | English |
Published |
London
Nature Publishing Group UK
26.10.2023
Nature Publishing Group |
Subjects | |
Online Access | Get full text |
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Summary: | Surface states of topological materials provide extreme electronic states for unconventional superconducting states. CaAg
1−
x
Pd
x
P is an ideal candidate for a nodal-line Dirac semimetal with drumhead surface states and no additional bulk bands. Here, we report that CaAg
1−
x
Pd
x
P has surface states that exhibit unconventional superconductivity (SC) around 1.5 K. Extremely sharp magnetoresistance, tuned by surface-sensitive gating, determines the surface origin of the ultrahigh-mobility “electrons.” The Pd-doping elevates the Fermi level towards the surface states, and as a result, the critical temperature (
T
c
) is increased up to 1.7 K from 1.2 K for undoped CaAgP. Furthermore, a soft point-contact study at the surface of Pd-doped CaAgP proved the emergence of unconventional SC on the surface. We observed the bell-shaped conductance spectra, a hallmark of the unconventional SC. Ultrahigh mobility carriers derived from the surface flat bands generate a new class of unconventional SC.
CaAg
1−
x
Pd
x
P is a nodal-line Dirac semimetal. Here, using ionic-liquid gated transport and soft point-contact spectroscopy, the authors show that this material realizes surface-confined unconventional superconductivity. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 2041-1723 2041-1723 |
DOI: | 10.1038/s41467-023-42535-5 |