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Related papers: Surface Superconductivity in Niobium for Supercond…

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We report on an effort to improve the performance of superconducting radiofrequency cavities by the use of heat treatment in a temperature range sufficient to dissociate the natural surface oxide. We find that the residual resistance is…

Accelerator Physics · Physics 2020-01-22 S. Posen , A. Romanenko , A. Grassellino , O. S. Melnychuk , D. A. Sergatskov

Here we report a novel nitridation technique for transforming niobium into hexagonal Nb2N which appears to be superconducting below 1K. The nitridation is achieved by high temperature annealing of Nb films grown on Si3N4/Si (100) substrate…

We present an experimental characterisation of the electrical properties of 3D-printed Niobium. The study was performed by inserting a 3D-printed Nb post inside an Aluminium cylindrical cavity, forming a 3D lumped element re-entrant…

The upper critical field $H_{c2} $, the field $H_{c3}$ for nucleation of the surface superconductivity, and the thermodynamic $H_c $ are evaluated within the weak-coupling theory for the isotropic s-wave case and arbitrary transport and…

Superconductivity · Physics 2024-11-28 V. G. Kogan , R. Prozorov

Even when cooled through its transition temperature in the presence of an external magnetic field, a superconductor can expel nearly all external magnetic flux. This Letter presents an experimental study to identify the parameters that most…

Transport and thermodynamic properties of a sintered pellet of the newly discovered $MgB_2$ superconductor have been measured to determine the characteristic critical magnetic fields and critical current densities. Both resistive transition…

Superconductivity · Physics 2009-11-07 D. K. Finnemore , J. E. Ostenson , S. L. Bud'ko , G. Lapertot , P. C. Canfield

Recently reported anomalies in frequency shift of order $\delta f\sim 0.1 -10\,\mbox{kHz}$ for Niobium SRF cavities in a narrow temperature region near $T_c\simeq 9\,\mbox{K}$ are sensitive to the surface preparation and Nitrogen doping. We…

Superconductivity · Physics 2023-11-27 Hikaru Ueki , Mehdi Zarea , J. A. Sauls

Nb3Sn (Tc ~ 18 K and Hsh ~ 400 mT) is a prospective material to replace Nb (Tc ~ 9 K and Hsh ~ 200 mT) in SRF accelerator cavities for significant cost reduction and performance enhancement. Because of its material properties, Nb3Sn is best…

Accelerator Physics · Physics 2020-04-22 Uttar Pudasaini , Grigory V. Eremeev , Charles E. Reece , James Tuggle , Michael J. Kelley

Electrical resistivity measurements as a function of temperature between 1 K and 300 K were performed at various pressures up to 3 GPa on the superconducting layered compounds Ln(O0.5F0.5)BiS2 (Ln = La, Ce). At atmospheric pressure,…

Superconductivity · Physics 2013-09-04 C. T. Wolowiec , D. Yazici , B. D. White , K. Huang , M. B. Maple

Superconductivity at about 15.6 K was achieved in Tb_{1-x}Ca_xFeAsO by partially substituting Tb^{3+} with Ca^{2+} in the nominal doping region x = 0.40 \sim 0.50. A detailed investigation was carried out in a typical sample with doping…

Superconductivity · Physics 2010-02-28 Gang Mu , Bin Zeng , Peng Cheng , Xiyu Zhu , Fei Han , Bing Shen , Hai-Hu Wen

We present magnetization measurements for the upper critical field $H_{c2}$ on aligned Na$_{x}$(H$_{3}$O)$_{z}$CoO$_{2}\cdot y$H$_{2}$O superconductors with magnetic field parallel to CoO$_2$ layers. The temperature-dependent part of the…

Superconductivity · Physics 2007-10-04 Zhi Ren , Chunmu Feng , Zhu'an Xu , Minghu Fang , Guanghan Cao

Magnetic flux trapped during the cooldown of superconducting radio-frequency cavities through the transition temperature due to incomplete Meissner state is known to be a significant source of radio-frequency losses. The sensitivity of flux…

Superconductivity · Physics 2020-03-04 Pashupati Dhakal , Gianluigi Ciovati , Alex Gurevich

In this paper, a comprehensive study of the effects of Ni-doping on structural, electrical, thermal and magnetic properties of the NbB2 is presented. Low amounts (\leq 10 %) of Ni substitution on Nb sites cause structural distortions and…

Superconductivity · Physics 2019-02-18 S. T. Renosto , R. Lang , E. Diez , L. E. Corrêa , M. S. da Luz , Z. Fisk , A. J. S. Machado

Nucleation of the pair condensate near surfaces above the upper critical magnetic field and the pair-condensate enhancement/suppression induced by changes in the electron-phonon interaction at interfaces are the most known examples of the…

Superconductivity · Physics 2023-10-18 Yunfei Bai , Libo Zhang , Xiaobing Luo , A. A. Shanenko , Yajiang Chen

We perform electric double-layer gating experiments on thin films of niobium nitride. Thanks to a cross-linked polymer electrolyte system of improved efficiency, we induce surface charge densities as high as $\approx 2.8 \times…

Two correlated superconducting phases are identified in layered superconductor BaTi2(Sb1-xBix)2O (x=0.16), with the superconducting transition temperatures of TC = 6 K (the high TC phase) and 3.4 K (the low TC Phase), respectively. The 6 K…

Superconductivity · Physics 2015-06-19 Y. Wu , X. L. Dong , M. W. Ma , H. X. Yang , C. Zhang , F. Zhou , X. J. Zhou , Z. X. Zhao

\beta-PdBi2 is one of the candidates for topological superconductors with a superconducting (SC) transition temperature (Tc) of 5.3 K, in which parity mixing of spin singlet and spin triplet has been anticipated, being crucial for the…

We have developped a novel lift-off process for fabrication of high quality superconducting submicron niobium structures. The process makes use of a thermostable polymer with a high transition temperature T_{g}= 235 C and an excellent…

Materials Science · Physics 2009-10-31 P. Dubos , P. Charlat , Th. Crozes , P. Paniez , B. Pannetier

We report the observation of superconductivity with multiple magnetic ordering and Rashba-type spin-orbit coupling in a layered polar semimetal EuAuBi. Magnetic transition is observed at 4 K, followed by a superconducting transition at 2.2…

Nitrogen doping study on niobium (Nb) samples used for the fabrication of the superconducting radio frequency (SRF) cavities has been carried out. The samples' surface treatment was attempted to replicate that of the SRF cavities, which…

Accelerator Physics · Physics 2018-04-23 Ziqin Yang , Xiangyang Lu , Yuan He , Weiwei Tan , Shichun Huang , Hao Guo