Magnetic Moment Formation in Quantum Point Contacts

Abstract

We study the formation of local magnetic moments in quantum point contacts. Using a Hubbard-like model to describe point contacts formed in a two dimensional system, we calculate the magnetic moment using the unrestricted Hartree approximation. We analyze different type of potentials to define the point contact, for a simple square potential we calculate a phase diagram in the parameter space (Coulomb repulsion - gate voltage). We also present an analytical calculation of the susceptibility to give explicit conditions for the occurrence of a local moment, we present a simple scaling argument to analyze how the stability of the magnetic moment depends on the point contact dimensions.

7 pages, 2 figures

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Cited by in corpus (5)

• Effects of short-range interactions on transport through quantum point contacts: A numerical approach
• Electron-electron interaction effects in quantum point contacts
• Entanglement between static and flying qubits in quantum wires
• Localized magnetic states in Rashba dots
• Influence of Magnetic Moment Formation on the Conductance of Coupled Quantum Wires