Functional Renormalization Group treatment of the 0.7-analog in quantum point contacts

Abstract

We use a recently developed fRG method (extendend Coupled-Ladder Approximation) to study the 0.7-analog in quantum point contacts, arising at the crossing of the 1st and 2nd band at suf- ficiently high magnetic fields. We reproduce the main features of the experimentally observed magnetic field dependence of the conductance at the 0.7-analog, using a QPC model with two bands and short-range interactions. In particular, we reproduce the fact that this dependence is quali- tatively different, depending on whether the analog is approached from higher or lower magnetic fields. We show that this effect can be explained qualitatively within a simple Hartree picture for the influence of the lowest electrons.

arXiv comment7 pages, 11 figures

References in corpus (5)

• Transmission Probability for Interacting Electrons Connected to Reservoirs
• Electron-electron interaction effects in quantum point contacts
• Energy-level pinning and the 0.7 spin state in one dimension: GaAs quantum wires studied using finite-bias spectroscopy
• The theory of the "0.7 anomaly" in quantum point contacts
• Functional Renormalization Group Approach for Inhomogeneous One-Dimensional Fermi Systems with Finite-Ranged Interactions

Cited by in corpus (1)

• Observation of the spin-orbit gap in bilayer graphene by one-dimensional ballistic transport