arXiv subjects

V. M. Gvozdikov

Publications and source records attributed to V. M. Gvozdikov.

3 recordsLinked to original sources

arXiv2005

Incoherence and enhanced magnetic quantum oscillations in the mixed state of a layered organic superconductor

We present a theory which is able to explain enhanced magnetic quantum-oscillation amplitudes in the superconducting state of a layered metal with incoherent electronic transport across the layers. The incoherence acts through the deformation of the layer-stacking factor which becomes complex and decreases the total scattering rate in the mixed state. This novel mechanism can compensate the usual decrease of the Dingle factor below the upper critical magnetic field caused by the intralayer scattering.

cond-mat.supr-con↗

arXiv2005

Magnetic Quantum Oscillations of the Conductivity in Two-dimensional Conductors with Localization

An analytic theory is developed for the diagonal conductivity $σ_{xx}$ of a 2D conductor which takes account of the localized states in the broaden Landau levels. In the low-field region $σ_{xx}$ display the Shubnikov-de Haas oscillations which in the limit $Ωτ\gg 1$ transforms into the sharp peaks ($Ω$ is the cyclotron frequency, $τ$ is the electron scattering time). Between the peaks $σ_{xx}\to 0$. With the decrease of temperature, $T$, the peaks in $σ_{xx}$ display first a thermal activation behavior $σ_{xx}\propto \exp(-Δ/T)$, which then crosses over into the variable-range-hopping regime at lower temperatures with $σ_{xx}\propto 1/T \exp(-\sqrt{T_{0}/T})$ (the prefactor 1/T is absent in the conductance).

cond-mat.mes-hall↗

arXiv2004

Spin-zero anomaly in the magnetic quantum oscillations of a two-dimensional metal

We report on an anomalous behavior of the spin-splitting zeros in the de Haas-van Alphen (dHvA) signal of a quasi-two-dimensional organic superconductor. The zeros as well as the angular dependence of the amplitude of the second harmonic deviate remarkably from the standard Lifshitz-Kosevich (LK) prediction. In contrast, the angular dependence of the fundamental dHvA amplitude as well as the spin-splitting zeros of the Shubnikov-de Haas signal follow the LK theory. We can explain this behavior by small chemical-potential oscillations and find a very good agreement between theory and experiment. A detailed wave-shape analysis of the dHvA signal corroborates the existence of an oscillating chemical potential.

cond-mat.str-el↗