Terahertz spectroscopy evidence of possible 40 K superconductivity in rhenium-doped strontium ruthenates

Yurii Aleshchenko; Boris Gorshunov; Elena Zhukova; Andrey Muratov; Alexander Dudka; Rajendra Dulal; Serafim Teknowijoyo; Sara Chahid; Vahan Nikoghosyan; Armen Gulian

doi:10.1103/physrevresearch.2.042020

arXiv · 2007.06509

Terahertz spectroscopy evidence of possible 40 K superconductivity in rhenium-doped strontium ruthenates

Yurii Aleshchenko·Boris Gorshunov·Elena Zhukova·Andrey Muratov·Alexander Dudka·Rajendra Dulal·Serafim Teknowijoyo·Sara Chahid·Vahan Nikoghosyan·Armen Gulian

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Abstract

Strontium ruthenates have many similarities with copper oxide superconductors and are of particular interest for the investigation of the mechanisms and conditions which lead to high-temperature superconductivity. We report here on multiple experimental indications of superconductivity with onset at 40 K in strontium ruthenate doped by rhenium and selenium with chlorine used as the flux. The main experimental evidence arises from terahertz spectroscopy of this material followed by AC and DC magnetization, as well as measurements of its heat capacity and magnetoresistance. Structural and morphological studies revealed the heterophase nature of this polycrystalline material as well as the changes of lattice parameters relative to the original phases. Experimental data show a higher critical temperature on the surface compared to that of the bulk of the sample.

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Yurii Aleshchenko, Boris Gorshunov, Elena Zhukova, Andrey Muratov, Alexander Dudka, Rajendra Dulal, Serafim Teknowijoyo, Sara Chahid, Vahan Nikoghosyan, Armen Gulian. 2020-07-02. Terahertz spectroscopy evidence of possible 40 K superconductivity in rhenium-doped strontium ruthenates. https://doi.org/10.1103/physrevresearch.2.042020

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