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 Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Recently superconductivity at 9 - 15 K was discovered in an infinite-layernickelate (Nd$_{0.8}$Sr$_{0.2}$NiO$_2$ films), which has received enormousattention. Since the $Ni^{1+}$ ionic state in NdNiO$_2$ may have the $3d^9$outer-shell electronic orbit which resembles that of the cuprates, it is verycurious to know whether superconductivity discovered here has similar mechanismas that in the cuprates. By using a three-step method, we successfullysynthesize the bulk samples of Nd$_{1-x}$Sr$_x$NiO$_2$ (x=0, 0.2, 0.4). TheX-ray diffractions reveal that all the samples contain mainly the infinitelayer phase of 112 with some amount of segregated Ni. This has also been wellproved by the SEM image and the EDS composition analysis. The resistivemeasurements on the Sr doped samples show insulating behavior without thepresence of superconductivity. Temperature dependence of the magnetic momentunder high magnetic fields exhibits a Curie-Weiss law feature with theparamagnetic moment of about 2$\mu_B$/f.u.. By applying pressure onNd$_{0.8}$Sr$_{0.2}$NiO$_2$ up to about 50.2 GPa, we find that the stronginsulating behavior at ambient pressure is significantly suppressed, butsuperconductivity has not been observed either. Since the lattice constantsderived from our XRD data are very close to those of the reportedsuperconducting films, we argue that the superconductivity in the reported filmmay not originate from the expected Nd$_{0.8}$Sr$_{0.2}$NiO$_2$, but arise fromthe interface or the stress effect.

Absence of superconductivity in bulk Nd$_{1-x}$Sr$_x$NiO$_2$