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Related papers: Fluctuation Magnetoconductance in MgB2

200 papers

We report on a simple calculation of the magnetotransport in cuprate superconductors, based on the nearly antiferromagnetic Fermi liquid (spin fluctuation) model. We find that the model explains all important features seen experimentally:…

Condensed Matter · Physics 2007-05-23 Branko Stojkovic , David Pines

The hydrostatic pressure effect on the newly discovered superconductor MgB2 has been determined. The transition temperature Tc was found to decrease linearly at a large rate of -1.6 K/GPa, in good quantitative agreement with the ensuing…

Superconductivity · Physics 2009-11-07 B. Lorenz , R. L. Meng , C. W. Chu

The flux flow resistivity associated with purely viscous motion of vortices in high-quality MgB_2 was measured by microwave surface impedance. Flux flow resistivity exhibits unusual field dependence with strong enhancement at low field,…

Superconductivity · Physics 2009-11-10 A. Shibata , M. Matsumoto , K. Izawa , Y. Matsuda , S. Lee , S. Tajima

The discovery of superconductivity at 39 K in MgB2[1] raises many issues. One of the central questions is whether this new superconductor resembles a high-temperature-cuprate superconductor or a low-temperature metallic superconductor in…

We perform a multifractal detrended fluctuation analysis of the magnetoconductance data of two standard types of mesoscopic systems: a disordered nanowire and a ballistic chaotic billiard, with two different lattice structures. We observe…

Mesoscale and Nanoscale Physics · Physics 2021-12-08 N. L. Pessoa , A. L. R. Barbosa , G. L. Vasconcelos , A. M. S. Macêdo

We show that above the critical temperature of superconductor - metal phase transitions, both the longitudinal and Hall conductivity exhibit strong temperature dependent mesoscopic fluctuations, with amplitudes much larger than the…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 F. Zhou , C. Biagini

We derive the fluctuational magnetization and the paraconductivity of Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) superconductors in their normal state. The FFLO superconducting fluctuations induce oscillations of the magnetization between…

Superconductivity · Physics 2009-07-04 François Konschelle , Jérôme Cayssol , Alexandre I. Buzdin

Measurements of conductance $G$ on short, wide, high-mobility Si-MOSFETs reveal both a two-dimensional metal-insulator transition (MIT) at moderate temperatures (1 $<~ T <$ 4~K) and mesoscopic fluctuations of the conductance at low…

Strongly Correlated Electrons · Physics 2009-10-30 K. P. Li , Dragana Popovic , S. Washburn

The mechanism of superconductivity in Pr$_2$Ba$_4$Cu$_7$O$_{15-\delta}$ is studied using a quasi-one dimensional double chain model with appopriate hopping integrals, on-site $U$, and off-site repulsion $V_1$. Applying the fluctuation…

Superconductivity · Physics 2009-11-13 Tsuguhito Nakano , Kazuhiko Kuroki , Seiichiro Onari

We report on measurements of the magnetoconductance of an open circular InGaAs quantum dot between 1.3K and 204K. We observe two types of magnetoconductance fluctuations: universal conductance fluctuations (UCFs), and 'focusing'…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 B. Hackens , S. Faniel , F. Delfosse , C. Gustin , H. Boutry , I. Huynen , X. Wallaert , S. Bollaert , A. Cappy , V. Bayot

We have studied the magnetic excitations in Ca$_{2-x}$Sr$_x$RuO$_4$, x=0.52 and 0.62, which exhibit an anomalous high susceptibility and heavy mass Fermi liquid behavior. Our inelastic neutron scattering experiments reveal strongly enhanced…

Strongly Correlated Electrons · Physics 2016-08-31 O. Friedt , P. Steffens , M. Braden , Y. Sidis , S. Nakatsuji , Y. Maeno

Alkali-doped fullerides are strongly correlated organic superconductors that exhibit high transition temperatures, exceptionally large critical magnetic fields and a number of other unusual properties. The proximity to a Mott insulating…

In-plane electrical transport properties of MgB2 single crystals grown under high pressure of 4-6 GPa and temperature of 1400-1700oC in Mg-B-N system have been measured. For all specimens we found sharp superconducting transition around…

Superconductivity · Physics 2009-11-07 Yu. Eltsev , S. Lee , K. Nakao , N. Chikumoto , S. Tajima , N. Koshizuka , M. Murakami

We have experimentally investigated the magnetisation of a mesoscopic aluminum loop at temperatures well below the superconducting transition temperature $T_{c}$. The flux quantisation of the superconducting loop was investigated with a…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 S. Pedersen , G. R. Kofod , J. C. Hollingbery , C. B. Sørensen , P. E. Lindelof

Magnetic fluctuations near to quantum criticality can have profound effects. They lead to characteristic scaling at high temperature which may ultimately give way to a reconstruction of the phase diagram and the formation of new phases at…

Strongly Correlated Electrons · Physics 2015-06-15 G. J. Conduit , C. J. Pedder , A. G. Green

The paraconductivity, originating from critical superconducting order-parameter fluctuations in the vicinity of the critical temperature in a layered superconductor is calculated in the frame of the self-consistent Hartree approximation,…

Superconductivity · Physics 2009-11-10 I. Puica , W. Lang

Commensurability oscillations in the magnetoresistivity of a two-dimensional electron gas in a two-dimensional lateral superlattice are studied in the framework of quasiclassical transport theory. It is assumed that the impurity scattering…

Disordered Systems and Neural Networks · Physics 2009-11-07 A. D. Mirlin , E. Tsitsishvili , P. Woelfle

We synthesized single crystalline and policrystalline MgB_2 under ambient pressures. The single crystals of MgB_2 were of good quality, where the crystal structure refinements were successfully converged with R = 0.020. The specific heat of…

Superconductivity · Physics 2009-11-07 Y. Machida , S. Sasaki , H. Fujii , M. Furuyama , I. Kakeya , K. Kadowaki

We derive Ginzburg-Landau-like action for two-dimensional disordered superconductor under far-from-equilibrium conditions in a fluctuational regime. Then, utilizing it, we calculate fluctuation induced density of states, Maki-Thomson and…

Superconductivity · Physics 2015-05-28 A. Petkovic , N. M. Chtchelkatchev , V. M. Vinokur

We report on measurements of the magnetic moment in superconducting MgB2 single crystals. We find \mu_0H_{c2}^c(0) = 3.2 T, \mu_0H_{c2}^{ab}(0) = 14.5 T, \gamma = 4.6, \mu_0H_c(0) = 0.28 T, and \kappa(T_c) = 4.7. The standard…

Superconductivity · Physics 2009-11-07 M. Zehetmayer , M. Eisterer , H. W. Weber , J. Jun , S. M. Kazakov , J. Karpinski , A. Wisniewski