Ferromagnetic Spin Coupling as the Origin of 0.7 Anomaly in Quantum Point Contacts

Abstract

We study one-dimensional itinerant electron models with ferromagnetic coupling to investigate the origin of 0.7 anomaly in quantum point contacts. Linear conductance calculations from the quantum Monte Carlo technique for spin interactions of different spatial range suggest that $0.7(2e^2/h)$ anomaly results from a strong interaction of low-density conduction electrons to ferromagnetic fluctuations formed across the potential barrier. The conductance plateau appears due to the strong incoherent scattering at high temperature when the electron traversal time matches the time scale of dynamic ferromagnetic excitations.

5 pages, 4 figures

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Cited by in corpus (10)

• Spin fluctuations in the 0.7-anomaly in quantum point contacts
• Effect of spin-orbit interactions on the 0.7 anomaly in quantum point contacts
• Functional Renormalization Group Approach for Inhomogeneous One-Dimensional Fermi Systems with Finite-Ranged Interactions
• Dependence of the 0.7 anomaly on the curvature of the potential barrier in quantum wires
• Scanning Gate Imaging of quantum point contacts and the origin of the 0.7 Anomaly
• Quantised conductance of one-dimensional strongly-correlated electrons in an oxide heterostructure
• Dirac's method for constraints - an application to quantum wires,the 0.7 conductance anomaly
• A Scaling Approach for Interacting Quantum Wires -a Possible Explanation for the 0.7 Anomalous Conductance
• Large Zeeman Splitting in Out-of-Plane Magnetic Field in a Double-Layer Quantum Point Contact
• On-chip quantum sensing of Kondo spins in a high-mobility quasi-one-dimensional nanoconstriction