Quantum transport in ferromagnetic Permalloy nanostructures

Abstract

We studied phase coherent phenomena in mesoscopic Permalloy samples by exploring low temperature transport. Both, differential conductance as a function of bias voltage and magnetoconductance of individual wires display conductance fluctuations. Analysis of these fluctuations yields a phase coherence length of $\sim 250$ nm at 25 mK as well as a $1/\sqrt{T}$ temperature dependence. To suppress conductance fluctuations by ensemble averaging we investigated low temperature transport in wire arrays and extended Permalloy films. In these samples we have measured conductance corrections which stem from electron-electron interaction (EEI) but attempts to detect signatures of weak localization were without success.

References in corpus (6)

• Weak localization in GaMnAs: evidence of impurity band transport
• Weak localization in ferromagnetic (Ga,Mn)As nanostructures
• Dephasing in (Ga,Mn)As nanowires and rings
• Electron-electron interaction in 2D and 1D ferromagnetic (Ga,Mn)As
• Quantum coherence in a ferromagnetic metal: time-dependent conductance fluctuations
• Phase coherent transport in (Ga,Mn)As