On the Magnetic Nature of Quantum Point Contacts

Abstract

We present results for a model that describes a quantum point contact. We show how electron-electron correlations, within the unrestricted Hartree-Fock approximation, generate a magnetic moment in the point contact. Having characterized the magnetic structure of the contact, we map the problem onto a simple one-channel model and calculate the temperature dependence of the conductance for different gate voltages. Our results are in good agreement with experimental results obtained in GaAs devices and support the idea of Kondo effect in these systems.

arXiv comment7 pages, 4 figures

References in corpus (8)

• Possible Spin Polarization in a One-Dimensional Electron Gas
• The Low-Temperature Fate of the 0.7 Structure in a Point Contact: A Kondo-like Correlated State in an Open System
• Interaction Effects in a One-Dimensional Constriction
• Kondo model for the "0.7 anomaly" in transport through a quantum point contact
• Density dependent spin polarisation in ultra low-disorder quantum wires
• Many-body spin related phenomena in ultra-low-disorder quantum wires
• Local moment formation in quantum point contacts
• Transport through quantum dots in mesoscopic circuits

Cited by in corpus (8)

• Detection of spin polarized currents in quantum point contacts via transverse electron focusing
• Electron-electron interaction effects in quantum point contacts
• 0.7 Structure and Zero Bias Anomaly in Ballistic Hole Quantum Wires
• Localized magnetic states in Rashba dots
• Magnetic Moment Formation in Quantum Point Contacts
• Influence of Magnetic Moment Formation on the Conductance of Coupled Quantum Wires
• Dephasing in a quantum dot coupled to a quantum point contact
• Nuclear magnetic resonance probes for the Kondo scenario for the 0.7 feature in semiconductor quantum point contact devices