Correlation Driven Transport Asymmetries Through Coupled Spins

Abstract

Correlation is a fundamental statistical measure of order in interacting quantum systems. In solids, electron correlations govern a diverse array of material classes and phenomena such as heavy fermion compounds, Hunds metals, high-Tc superconductors, and the Kondo effect. Spin-spin correlations, notably investigated by Kaufman and Onsager in the 1940s 6, are at the foundation of numerous theoretical models but are challenging to measure experimentally. Reciprocal space methods can map correlations, but at the single atom limit new experimental probes are needed. Here, we determine the correlations between a strongly hybridized spin impurity and its electron bath by varying the coupling to a second magnetic impurity in the junction of a scanning tunneling microscope. Electronic transport through these coupled spins reveals an asymmetry in the differential conductance reminiscent of spin-polarized transport in a magnetic field. We show that at zero field, this asymmetry can be controlled by the coupling strength and is directly related to either ferromagnetic (FM) or antiferromagnetic (AFM) spin-spin correlations.

18 pages, 4 figures

References in corpus (8)

• Scanning tunneling spectroscopy of high-temperature superconductors
• Strong electronic correlations from Hund's coupling
• Spin Excitations and Correlations in Scanning Tunneling Spectroscopy
• Nonequilibrium Singlet-Triplet Kondo Effect in Carbon Nanotubes
• Spintronic magnetic anisotropy
• Quantum Engineering of Spin and Anisotropy in Magnetic Molecular Junctions
• The Spin-Polarization of the Split Kondo State
• The emergence of classical behavior in magnetic adatoms

Cited by in corpus (8)

• Atomic-scale spin sensing with a single-molecule at the apex of a scanning tunneling microscope
• Probing Magnetic Excitations and Correlations in Single and Coupled Spin Systems with Scanning Tunneling Spectroscopy
• Exchange mechanism for electron paramagnetic resonance of individual adatoms
• Dynamical Negative Differential Resistance in Antiferromagnetically Coupled Few-Atom Spin-Chains
• Spin-driven electrical power generation at room temperature
• Sensing the spin of an individual Ce adatom
• Magnetoresistance and spintronic anisotropy induced by spin excitations along molecular spin chains
• Large effect of the metal substrate on the magnetic anisotropy of Co on hexagonal Boron Nitride