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

Iron-chalcogenide superconductor Fe$_{1.03}$Se$_{0.5}$Te$_{0.5}$ has beeninvestigated under high pressure using synchrotron based x-ray diffraction andmid-infrared reflectance measurements at room temperature. Pressure dependenceof the superconducting transition temperature (T$_c$) of the same sample hasbeen determined by temperature-dependent resistance measurements up to 10 GPa.Although the high pressure orthorhombic phase ($\textit{Pbnm}$) starts emergingat 4 GPa, structural transition becomes clearly observable above 10 GPa. Astrong correlation is observed between the Fe(Se,Te)$_{4}$ tetrahedraldeformation in the tetragonal phase ($\textit{P4/nmm}$) and the sharp rise ofT$_c$ up to $\sim$4 GPa, above which T$_c$ is found to be almost pressureindependent at least up to 10 GPa. A subtle structural modification of thetetragonal phase is noticed above 10 GPa, suggesting a structural transitionwith possible Fe$^{2+}$ spin-state transition. The evolution with pressure ofthe optical conductivity shows that the Drude term increases systematicallywith pressure up to 5.4 GPa, indicating the evolution of the tetragonal phasetowards a conventional metallic state. At further higher pressures the Drudeterm reduces drastically implying a poor metallic character of the highpressure orthorhombic phase. Our results suggest that occurrence of large onsetT$_c$ above 4 GPa is due to a systematic increase of high pressure orthorhombicphase fraction.

Structural and optical investigations of the iron-chalcogenide superconductor Fe$_{1.03}$Se$_{0.5}$Te$_{0.5}$ under high pressure