Weak Localization and Magnetoconductance in Percolative Superconducting Aluminum Films

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Yamada, Kazumasa, Shinozaki, Bunjyu, Kawaguti, Takashi
Natura: Preprint
Pubblicazione: 2026
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866914408870969344
author Yamada, Kazumasa
Shinozaki, Bunjyu
Kawaguti, Takashi
author_facet Yamada, Kazumasa
Shinozaki, Bunjyu
Kawaguti, Takashi
contents In order to investigate the crossover from the homogeneous behavior to inhomogeneous (percolative) one, the temperature $T$ and magnetic field H dependence of the sheet resistance $R_\square$ have been measured for two-dimensional granular aluminum films. Fitting the theory to data of magnetoconductance near $T_C$ with use of the diffusion constant $D(T)$ as a fitting parameter, we have obtained the anomalous $T$-dependent diffusion constant $D$. From the analysis of $D(T)$, the electron diffusion index $θ$, a certain critical exponent in percolation theory, has been obtained. In the relation $R_\square-θ$, the value of $θ$ varies abruptly near $1.5kω$. This behavior suggesting the above mentioned crossover is similar to our previous results determined from the temperature dependence of the upper critical field. For percolative films in $H = 5\mathrm{T}$, we have found the strong $R_\square$ dependence of the prefactor $α_T$ in the expression$σ=[α_T e^2/(2π^2\hbar)]\ln T+σ_0$. The relation $α_T\propto1/R_\square$ can be explained qualitatively by a model of scaling law for percolation.
format Preprint
id arxiv_https___arxiv_org_abs_2603_18684
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Weak Localization and Magnetoconductance in Percolative Superconducting Aluminum Films
Yamada, Kazumasa
Shinozaki, Bunjyu
Kawaguti, Takashi
Superconductivity
In order to investigate the crossover from the homogeneous behavior to inhomogeneous (percolative) one, the temperature $T$ and magnetic field H dependence of the sheet resistance $R_\square$ have been measured for two-dimensional granular aluminum films. Fitting the theory to data of magnetoconductance near $T_C$ with use of the diffusion constant $D(T)$ as a fitting parameter, we have obtained the anomalous $T$-dependent diffusion constant $D$. From the analysis of $D(T)$, the electron diffusion index $θ$, a certain critical exponent in percolation theory, has been obtained. In the relation $R_\square-θ$, the value of $θ$ varies abruptly near $1.5kω$. This behavior suggesting the above mentioned crossover is similar to our previous results determined from the temperature dependence of the upper critical field. For percolative films in $H = 5\mathrm{T}$, we have found the strong $R_\square$ dependence of the prefactor $α_T$ in the expression$σ=[α_T e^2/(2π^2\hbar)]\ln T+σ_0$. The relation $α_T\propto1/R_\square$ can be explained qualitatively by a model of scaling law for percolation.
title Weak Localization and Magnetoconductance in Percolative Superconducting Aluminum Films
topic Superconductivity
url https://arxiv.org/abs/2603.18684