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 Tools annual

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 monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

We report both 77Se and 87Rb NMR studies on Tl0.47Rb0.34Fe1.63Se2single-crystalline superconductors (T_c about 32 K). Singlet superconductivityis decisively determined by a sharp drop of the Knight shift K(T) below T_c,after subtracting the superconducting diamagnetic effect. However, theHebel-Slichter coherence peak below T_c is not observed in the spin-latticerelaxation rate 1/T_1, even with a low in-plane NMR field of 2.6 Tesla. Justabove T_c, no evidence of low-energy spin fluctuation is found in thespin-lattice relaxation rate on both the 77Se and the 87Rb sites. Upon warming,however, the Knight shifts and the spin-lattice relaxation rates of both nucleiincrease substantially with temperature. In particular, the Knight shift isnearly isotropic and follow a function fit of K=a+bT^2 from T_c up to 300 K.These normal state properties may be an indication of thermally activated spinfluctuations. Our observations should put a strong constraint to the theory ofmagnetism and superconductivity in the newly discovered iron-basedsuperconductors.

Superconductivity and normal state properties of single-crystalline Tl0.47Rb0.34Fe1.63Se2 as seen via 77Se and 87Rb NMR