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Related papers: Weak localization effects in granular metals

200 papers

We study quantum interference corrections to the conductivity in (Ga,Mn)As ferromagnetic semiconductors using a model with disordered valence band holes coupled to localized Mn moments through a p-d kinetic-exchange interaction. We find…

Materials Science · Physics 2015-05-13 Ion Garate , Jairo Sinova , T. Jungwirth , A. H. MacDonald

We evaluate quantum corrections to conductivity in an electrically gated thin film of a three-dimensional (3D) topological insulator (TI). We derive approximate analytical expressions for the low-field magnetoresistance as a function of…

Mesoscale and Nanoscale Physics · Physics 2012-07-25 Ion Garate , Leonid Glazman

Weak localization corrections to conductivity of ferromagnetic systems are studied theoretically in the case when spin-orbit interaction plays a significant role. Two cases are analyzed in detail: (i) the case when the spin-orbit…

Materials Science · Physics 2009-11-07 V. K. Dugaev , P. Bruno , J. Barnas

We report the observation of negative magnetoresistance in the ferromagnetic semiconductor GaMnAs at low temperatures ($T<3$ K) and low magnetic fields ($0< B <20$ mT). We attribute this effect to weak localization. Observation of weak…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 L. P. Rokhinson , Y. Lyanda-Geller , Z. Ge , S. Shen , X. Liu , M. Dobrowolska , J. K. Furdyna

We study the dimensional crossover of weak localization in strongly anisotropic systems. This crossover from three-dimensional behavior to an effective lower dimensional system is triggered by increasing temperature if the phase coherence…

Disordered Systems and Neural Networks · Physics 2009-10-30 C. Mauz , A. Rosch , P. Woelfle

Weyl semimetals are topological materials that provide a condensed-matter realization of the chiral anomaly. A positive longitudinal magnetoconductance quadratic in magnetic field has been promoted as a diagnostic for this anomaly. By…

Mesoscale and Nanoscale Physics · Physics 2020-05-13 Andy Knoll , Carsten Timm , Tobias Meng

This paper is devoted to the temperature dependence of the resistivity in Si- MOS samples over the wide range of densities in the ``metallic phase'' (n>n_c) but not too close to the critical density n_c. Three domains of different behavior…

Strongly Correlated Electrons · Physics 2007-05-23 B. L. Altshuler , G. W. Martin , D. L. Maslov , V. M. Pudalov , A. Prinz , G. Brunthaler , G. Bauer

We present an undergraduate lab that investigates weak localization in thin silver films. The films prepared in our lab have thickness, $a$, between 60-200 \AA, a mesoscopic length scale. At low temperatures, the inelastic dephasing length…

Physics Education · Physics 2009-11-11 A. D. Beyer , M. Koesters , K. G. Libbrecht , E. D. Black

In situ transport measurements have been made on ultrathin ($<$100 {\AA} thick) polycrystalline Fe films as a function of temperature and magnetic field for a wide range of disorder strengths. For sheet resistances $R_{xx}$ less than $\sim…

Disordered Systems and Neural Networks · Physics 2009-11-11 P. Mitra , A. F. Hebard , K. A. Muttalib , P. Woelfle

We study Coulomb blockade effects in the thermodynamic quantities of a weakly disordered metallic grain coupled to a metallic lead by a tunneling contact with a large conductance $g_T$. We consider the case of broken time-reversal symmetry…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 I. S. Beloborodov , A. V. Andreev

Delocalization problem for a two-dimensional non-interacting electron system is studied under a random magnetic field. With the presence of a random magnetic field, the Hall conductance carried by each eigenstate can become nonzero and…

Condensed Matter · Physics 2016-08-31 D. N. Sheng , Z. Y. Weng

We compute the quantum correction due to weak localization for transport properties of disordered quasi-one-dimensional conductors, by integrating the Dorokhov-Mello-Pereyra-Kumar equation for the distribution of the transmission…

Condensed Matter · Physics 2007-05-23 C. W. J. Beenakker

The one-parameter scaling theory of localization predicts that all states in a disordered two-dimensional system with broken time reversal symmetry are localized even in the presence of strong spin-orbit coupling. While at constant strong…

Disordered Systems and Neural Networks · Physics 2017-06-27 Ying Su , C. Wang , Y. Avishai , Yigal Meir , X. R. Wang

We investigate the effects of magnetic and electric fields on electron wavefunction interactions in single walled carbon nanotube bundles. The magnetoresistance measurements performed at 4.2K and the dependence of the data upon the electric…

Mesoscale and Nanoscale Physics · Physics 2010-09-15 M. Salvato , M. Lucci , I. Ottaviani , M. Cirillo , S. Orlanducci , F. Toschi , M. L. Terranova

The first-order superconducting fluctuation corrections to the thermal conductivity of a granular metal are calculated. A suppression of thermal conductivity proportional to $T_c/(T-T_c)$ is observed in a region not too close to the…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 C. Biagini , R. Ferone , Rosario Fazio , F. W. J. Hekking , V. Tognetti

Transport properties of granular systems are governed by Coulomb blockade effects caused by the discreteness of the electron charge. We show that, in the limit of vanishing mean level spacing on the grains, the low-temperature behavior of…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Alexander Altland , Leonid I. Glazman , Alex Kamenev , Julia S. Meyer

We consider magnetotransport in a disordered two-dimensional electron gas in the presence of a periodic modulation in one direction. Existing quasiclassical and quantum approaches to this problem account for Weiss oscillations in the…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 G. Schwiete , D. Taras-Semchuk , K. B. Efetov

This is a study of phase-coherent conduction through a ballistic point contact with disordered leads. The disorder imposes mesoscopic (sample-to-sample) fluctuations and weak-localization corrections on the conductance, and also leads to…

Condensed Matter · Physics 2007-05-23 C. W. J. Beenakker , J. A. Melsen

A systematic study of the resistivity and Hall effect in single crystal Nd{2-x}Ce{x}CuO{4-d} films (0.12 < x < 0.20) is presented, with special emphasis on the low-temperature dependence of the normal state conductance. Two-dimensional weak…

Spontaneous intervalley coherence is suspected in several different graphene multilayer systems, but is difficult to confirm because of a paucity of convenient experimental signatures. Here we suggest that magneto-conductance features…

Mesoscale and Nanoscale Physics · Physics 2023-12-19 Nemin Wei , Yongxin Zeng , A. H. MacDonald