Magnetic-Field Universality of the Kondo Effect Revealed by Thermocurrent Spectroscopy
Chunwei Hsu, Theo A. Costi, David Vogel, Christina Wegeberg, Marcel Mayor, Herre S. J. van der Zant, Pascal Gehring
Abstract
Probing the universal low-temperature magnetic-field scaling of Kondo-correlated quantum dots via electrical conductance has proved to be experimentally challenging. Here, we show how to probe this in nonlinear thermocurrent spectroscopy applied to a molecular quantum dot in the Kondo regime. Our results demonstrate that the bias-dependent thermocurrent is a sensitive probe of universal Kondo physics, directly measures the splitting of the Kondo resonance in a magnetic field, and opens up possibilities for investigating nanosystems far from thermal and electrical equilibrium.
Topics & Concepts
Kondo effectUniversality (dynamical systems)Quantum dotCondensed matter physicsPhysicsKondo insulatorSpectroscopyScalingConductanceQuantumThermalResonance (particle physics)Quantum mechanicsNonlinear systemElectrical resistivity and conductivityThermal conductivityAnderson impurity modelQuantum and electron transport phenomenaAdvanced Physical and Chemical Molecular InteractionsSemiconductor Quantum Structures and Devices