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相关论文: Mesoscopic conductance effects in InMnAs structure…

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We report a comprehensive study of the complex AC conductivity of thin effectively 2D amorphous superconducting InO_x films at zero applied field. Below a temperature scale T_c0 where the superconducting order parameter amplitude becomes…

超导电性 · 物理学 2010-09-16 R. W. Crane , N. P. Armitage , A. Johansson , G. Sambandamurthy , D. Shahar , G. Gruner

We have measured the frequency and temperature dependences of complex ac conductivity, \sigma(\omega)=\sigma_1(\omega)-i\sigma_2(\omega), of NbN films in zero magnetic field between 0.1 to 10 GHz using a microwave broadband technique. In…

超导电性 · 物理学 2009-11-11 Takeyoshi Ohashi , Haruhisa Kitano , Astutaka Maeda , Hiroyuki Akaike , Akira Fujimaki

We present transport, Hall effect, electronic tunnelling and penetration depth studies in 3D homogeneously disordered epitaxial NbN thin films with disorder ranging from the moderately clean limit (k_Fl~10.12) to the very dirty limit…

The second order correction to free energy due to the interaction between electrons is calculated for a quasi-one-dimensional conductor exposed to a magnetic field perpendicular to the chains. It is found that specific heat, magnetization…

凝聚态物理 · 物理学 2009-10-22 Victor M. Yakovenko

We discuss the excess conductivity at nonzero frequencies in a superconductor above T_c within the gaussian approximation. We focus the attention on the temperature range not too close to T_c: within a time-dependent Ginzburg-Landau…

超导电性 · 物理学 2009-11-07 Enrico Silva

The normal-conducting state of the superconductor UTe$_2$ is studied by entropy analysis for magnetic fields along the $b$-axis, obtained from magnetization using the relation $(\partial M/\partial T)_B=(\partial S/\partial B)_T$. We…

超导电性 · 物理学 2024-04-23 Y. Tokiwa , . P. Opletal , H. Sakai , S. Kambe , E. Yamamoto , M. Kimata , S. Awaji , T. Sasaki , D. Aoki , Y. Haga , Y. Tokunaga

We investigate the evolution of superconductivity with decreasing film thickness in ultrathin amorphous MoGe (a-MoGe) films using a combination of sub-Kelvin scanning tunneling spectroscopy, magnetic penetration depth measurements and…

We study theoretically orbital effects of a parallel magnetic field applied to a disordered superconducting film. We find that the field reduces the phase stiffness and leads to strong quantum phase fluctuations driving the system into an…

超导电性 · 物理学 2013-07-31 Dganit Meidan , Yuval Oreg

Magnetism and superconductivity are physical phenomena whose foundations are rooted in quantum mechanics and whose technological applications do not cease to surprise us. In this article we describe a class of magnetic materials, we call…

超导电性 · 物理学 2007-05-23 C. D. Batista , G. Ortiz , A. V. Balatsky

We show that microstructures built from non-magnetic conducting sheets exhibit an effective magnetic permeability, /mu_meff, which can be tuned to values not accessible in naturally occurring materials, including large imaginary components…

应用物理 · 物理学 2025-07-03 JB Pendry , AJ Holden , DJ Robbins , WJ Stewart

Magnetoconductance fluctuations are used to study the effect of an applied bias on an electron billiard. At lower bias, nonlinear effects can be well described by electron heating alone, while at higher bias (V > 2mV, ~5% of the electron…

介观与纳米尺度物理 · 物理学 2015-06-25 C. A. Marlow , R. P. Taylor , M. Fairbanks , H. Linke

In mesoscopic systems conductance fluctuations are a sensitive probe of electron dynamics and chaotic phenomena. We show that the conductance of a purely classical chaotic system with either fully chaotic or mixed phase space generically…

介观与纳米尺度物理 · 物理学 2009-11-13 H. Hennig , R. Fleischmann , L. Hufnagel , T. Geisel

In one dimensional wires, fluctuations destroy superconducting long-range order and stiffness at finite temperatures; in an infinite wire, quasi-long range order and stiffness survive at zero temperature if the wire's dimensionless…

超导电性 · 物理学 2009-11-10 H. P. Büchler , V. B. Geshkenbein , G. Blatter

Critical fluctuations have been studied in the microwave conductivity of Bi_2Sr_2CaCu_2O_(8+\delta), Bi_2Sr_2Ca_2Cu_3O_(10+delta), and YBa_2Cu_3O_(7-delta) thin films above T_c. It is found that a consistent analysis of the real and…

超导电性 · 物理学 2009-11-10 D. -N. Peligrad , A. Dulcic , M. Mehring

Magnetic properties of $M_{c}$Ta$_{2}$S$_{2}$C ($M$ = Fe, Co, Ni, Cu) have been studied using SQUID DC and AC magnetic susceptibility. In these systems magnetic $M^{2+}$ ions are intercalated into van der Waals gaps between adjacent S…

超导电性 · 物理学 2008-10-02 Masatsugu Suzuki , Itsuko S. Suzuki , Jürgen Walter

Since the prediction of spin-gapless semiconducting behaviour in the Heusler compound Mn$_2$CoAl, evidence of spin-gapless behaviour in thin films has typically been inferred from magnetotransport measurements. The spin gapless state is…

The effect of fluctuation induced weakly first order phase transition known for three dimensional (3D) type I superconductors appears in a modified and strongly enhanced variant in thin (quasi-2D) superconducting films. The unusual…

超导电性 · 物理学 2009-11-07 R. Folk , D. V. Shopova , D. I. Uzunov

Conductions fluctuations (CF) are studied in single layer graphene devices with superconducting source and drain contacts made from aluminium. The CF are found to be enhanced by superconductivity by a factor of 1.4 to 2. This (near)…

介观与纳米尺度物理 · 物理学 2011-09-19 F. Freitag , J. Trbovic , C. Schönenberger

We derive a quantum-mechanical formula of the orbital magnetic quadrupole moment (MQM) in periodic systems by using the gauge-covariant gradient expansion. This formula is valid for insulators and metals at zero and finite temperature. We…

材料科学 · 物理学 2018-07-25 Atsuo Shitade , Hikaru Watanabe , Youichi Yanase

We report on the normal-superconducting phase transition in thick $\mathrm{YBa_{2}Cu_{3}O_{7-\delta}}$ films in zero magnetic field. We find significant finite-size effects at low currents even in our thickest films ($d = 3200$ \AA). Using…

超导电性 · 物理学 2009-11-10 M. C. Sullivan , D. R. Strachan , T. Frederiksen , R. A. Ott , M. Lilly , C. J. Lobb