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Related papers: Break-Junction Tunneling on MgB_2

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The progress in investigation of two-band superconductor MgB$_2$ by the point-contact spectroscopy (PCS) is given. Results of study of superconducting gap temperature and magnetic field dependence for two-dimensional $\sigma$ and…

Superconductivity · Physics 2007-05-23 I. K. Yanson , Yu. G. Naidyuk

We report the results of the first directional point-contact measurements in Mg(B_{1-x}C_{x})_2 single crystals with 0.047 <= x <= 0.132. The two-gap superconductivity typical of MgB_2 persists up to x=0.105. In this region, the values of…

We observe a subharmonic gap sturucture (SGS) and the Josephson effect in superconducting scanning tunneling microscope junctions with resistances below 100 kOhm. The magnitude of the n=2 SGS is shown to scale with the square of the…

Superconductivity · Physics 2007-05-23 O. Naaman , R. C. Dynes

Measurements of the penetration depth $\lambda (T,H)$ in the presence of a DC magnetic field were performed in $MgB_2$ wires. In as-prepared wires $\lambda (T,H<130 Oe)$ shows a strong diamagnetic downturn below $\approx 10 K$. A DC…

Superconductivity · Physics 2009-11-07 R. Prozorov , R. W. Giannetta , S. L. Bud'ko , P. C. Canfield

We have successfully fabricated micron-scale Cu-AlO$_{x} $-Al-NbN normal metal-insulator-superconductor (NIS) tunnel junction devices, using pulsed laser deposition (PLD) for NbN film growth, and electron-beam lithography and shadow…

Superconductivity · Physics 2013-09-27 S. Chaudhuri , M. R. Nevala , I. J. Maasilta

We report on the temperature dependence of the in plane magnetic penetration depth ($\lambda_{ab}$) and first penetration field ($H_f\propto 1/\lambda_{ab}^2(T)$ for $H\|c$) in 2H-NbS$_2$ single crystals. An exponential temperature…

Superconductivity · Physics 2015-06-12 Pascale Diener , Maxime Leroux , Laurent Cario , Thierry Klein , Pierre Rodiere

Here presented a systematic study of superconductor-constriction-superconductor contacts realized by a break-junction technique in layered superconductors. Depending on the constriction transparency the tunneling and SnS-Andreev…

Superconductivity · Physics 2017-08-23 S. A. Kuzmichev , T. E. Kuzmicheva

Superfluid condensation can fundamentally be different from that predicted by the Bardeen-Cooper-Schrieffer (BCS) theory. In a broad class of low-carrier-density superconductors, such as granular aluminum, doped nitrides, and high-Tc…

Superconductivity · Physics 2024-09-27 L. Pisani , A. G. Moshe , P. Pieri , G. Calvanese Strinati , G. Deutscher

We have studied the structure of the superconducting gap in MgB2 thin films by means of point-contact spectroscopy using a gold tip. The films were produced by depositing pure boron on a sapphire substrate, using e-beam evaporation,…

Superconducting order parameter and its symmetry are important parameters towards deciphering the pairing mechanism in newly discovered superconducting systems. We report a study on penetration depth measurement on Nb2PdS5 that has recently…

Superconductivity · Physics 2016-04-20 Shruti , R. Goyal , V. P. S Awana , S. Patnaik

One of the most important predictions of the two-gap theory of superconductivity concerns the role of interband scattering (IBS) by impurities. IBS is expected to decrease the critical temperature, Tc, of MgB2 to a saturation value of about…

Superconductivity · Physics 2009-11-11 M. Putti , P. Brotto , M. Monni , E. Galleani , A. Sanna , S. Massidda

Van der Waals (vdW) Josephson junctions can possibly accelerate the development of advanced superconducting device that utilizes the unique properties of two-dimensional (2D) transition metal dichalcogenide (TMD) superconductors such as…

Superconductivity · Physics 2022-11-17 Chuanwen Zhao , Xin Yi , Qiao Chen , Chengyu Yan , Shun Wang

The two gaps in a two-band clean s-wave superconductor are evaluated self-consistently within the quasiclassical Eilenberger weak-coupling formalism with two in-band and one inter-band pairing potentials. Superfluid density, free energy and…

Superconductivity · Physics 2009-10-28 V. G. Kogan , C. Martin , R. Prozorov

Break junctions made of the optimally doped high temperature superconductor Bi2Sr2Ca2CuO8 with Tc of 90 K has been investigated in magnetic fields up to 12 T, at temperatures from 4.2 K to Tc. The junction resistance varied between 1kOhm…

Superconductivity · Physics 2007-05-23 G. Mihaly , A. Halbritter , L. Mihaly , L. Forro

Superconductivity has been first observed in TlNi$_2$Se$_2$ at T$_C$=3.7 K and appears to involve heavy electrons with an effective mass $m^*$=14$\sim$20 $m_b$, as inferred from the normal state electronic specific heat and the upper…

Superconductivity · Physics 2013-11-20 Hangdong Wang , Chiheng Dong , Qianhui Mao , Rajwali Khan , Xi Zhou , Zhenxia Li , Bin Chen , Jinhu Yang , Qiping Su , Minghu Fang

New tunneling data are reported in underdoped Bi2Sr2CaCu2O8-d using superconductor-insulator-superconductor break junctions. Energy gaps, Delta, of 51+2, 54+2 and 57+3 meV are observed for three crystals with Tc=77, 74, and 70 K…

Superconductivity · Physics 2009-10-31 N. Miyakawa , J. F. Zasadzinski , L. Ozyuzer , P. Guptasarma , D. G. Hinks , C. Kendziora , K. E. Gray

We have studied the quasiparticle excitation spectrum of the superconductor Ba8Si46 by local tunneling spectroscopy. Using high energy resolution achieved in Superconductor-Superconductor junctions we observed tunneling conductance spectra…

Sub-Kelvin scanning tunnelling spectroscopy in the Chevrel Phases SnMo6S8 and PbMo6S8 reveals two distinct superconducting gaps with Delta_1 = 3 meV, Delta_2 ~ 1.0 meV and Delta_1 = 3.1 meV, Delta_2 ~ 1.4 meV respectively. The gap…

In the present investigation (2002) the current-voltage characteristics (CVCs) of break junctions in polycrystalline $MgB_2$ samples have been studied in the temperature range $4.2 K < T < T_c$. An inelastic Cooper pair tunneling…

We present the first results of directional point-contact measurements in Mg_{1-x}Mn_{x}B_2 single crystals, with x up to 0.015 and bulk T_c down to 13.3 K. The order parameters Delta_{sigma} and Delta_{pi} were obtained by fitting the…