Critical current density and vortex pinning in tetragonalFeS1−xSex(x=0,0.06)

Abstract

We report critical current density (Jc) in tetragonal FeS single crystals, similar to iron based superconductors with much higher superconducting critical temperatures (Tc's). The Jc is enhanced 3 times by 6% Se doping. We observe scaling of the normalized vortex pinning force as a function of reduced field at all temperatures. Vortex pinning in FeS and FeS0.94Se0.06 shows contribution of core-normal surface-like pinning. Reduced temperature dependence of Jc indicates that dominant interaction of vortex cores and pinning centers is via scattering of charge carriers with reduced mean free path (δl), in contrast to KxFe2−ySe2 where spatial variations in Tc (δTc) prevails.

Direct evidence of two superconducting gaps in FeSe0.5Te0.5: SnS-Andreev spectroscopy and the lower critical field

“…However, as it was shown for several types of 11 family single crystal materials (FeSe - [30], FeS, FeSeS - [32], FeSeTe - [33,34] magnetic hysteresis loops are symmetric close to the critical temperatures of these materials, which means the absence of surface barriers and thus validating the determination of H c1 (T ) by means of deviation from linear Meissner behaviour criterium.…”

Electronic structure of FeS

“…[13,24], and the phase diagram, including the Tcs for FeSe1−xTex and FeSe1−xSx were taken from Refs. [10,15,38,39]. Two regions of the SC dome marked by black dashed lines are inferred based on interpolation, in the absence of any report on these substitution.…”

Implementation Security Certification of Decoy‐BB84 Quantum Key Distribution Systems

“…[22] It has been noticed that pulses containing two or more photons from commonly used light source (heavily attenuated laser) will degrade the final key late proportional to the square of transmittance by photon-number-splitting (PNS) attack. [23] Decoy method was proposed as a countermeasure of the PNS attack, [24][25][26] where Akihisa Tomita received the B.S. and M.S.…”

“…Since Eve may select the pulses for her benefit in the channel of transmittance η, the imbalance will increase as = ημ (25) for the pulses of mean photon number μ.…”