Ferromagnetically coupled magnetic impurities in a quantum point contact

Abstract

We investigate the ground and excited states of interacting electrons in a quantum point contact using exact diagonalization method. We find that strongly localized states in the point contact appear when a new conductance channel opens due to momentum mismatch. These localized states form magnetic impurity states which are stable in a finite regime of chemical potential and excitation energy. Interestingly, these magnetic impurities have ferromagnetic coupling, which shed light on the experimentally observed puzzling coexistence of Kondo correlation and spin filtering in a quantum point contact.

References in corpus (10)

• 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
• Kondo model for the "0.7 anomaly" in transport through a quantum point contact
• Kondo effect in real quantum dots
• Density dependent spin polarisation in ultra low-disorder quantum wires
• Magnetic impurity formation in quantum point contacts
• Spontaneous spin polarization in quantum point contacts
• Local moment formation in quantum point contacts
• Fano factor reduction on the 0.7 structure in a ballistic one-dimensional wire
• Localization in an Inhomogeneous Quantum Wire

Cited by in corpus (7)

• What lurks below the last plateau: Experimental studies of the 0.7 x 2e^2/h conductance anomaly in one-dimensional systems
• Evidence for the Formation of Quasi-Bound-State in an Asymmetrical Quantum Point Contact
• Tuning the Fano Resonance with an Intruder Continuum
• Evidence for Charging Effects in CdTe/CdMgTe Quantum Point Contacts
• Temperature Modulation of the Transmission Barrier in Quantum Point Contacts
• Detecting weak coupling in mesoscopic systems with a nonequilibrium Fano resonance
• Quasibound States and Evidence for a Spin 1 Kondo Effect in Asymmetric Quantum Point Contacts