Quantum Criticality in Ferromagnetic Single-Electron Transistors

Abstract

Considerable evidence exists for the failure of the traditional theory of quantum critical points (QCPs), pointing to the need to incorporate novel excitations. The destruction of Kondo entanglement and the concomitant critical Kondo effect may underlie these emergent excitations in heavy fermion metals -- a prototype system for quantum criticality -- but the effect remains poorly understood. Here, we show how ferromagnetic single-electron transistors can be used to study this effect. We theoretically demonstrate a gate-voltage induced quantum phase transition. The critical Kondo effect is manifested in a fractional-power-law dependence of the conductance on temperature ($T$). The AC conductance and thermal noise spectrum have related power-law dependences on frequency ($\omega$) and, in addition, show an $\omega /T$ scaling. Our results imply that the ferromagnetic nanostructure constitutes a realistic model system to elucidate magnetic quantum criticality that is central to the heavy fermions and other bulk materials with non-Fermi liquid behavior.

16 pages, 4 figures; references added and typo in the critical exponent for the paramagnon case corrected; as published in PNAS

References in corpus (27)

• Kondo Physics in a Single Electron Transistor
• Gapless Spin-Fluid Ground State in a Random Quantum Heisenberg Magnet
• A Tunable Kondo Effect in Quantum Dots
• Locally critical quantum phase transitions in strongly correlated metals
• Quantum criticality
• Hall-effect evolution across a heavy-fermion quantum critical point
• The Kondo effect in C${}_{60}$ single-molecule transistors
• Singular Fermi Liquids
• Tunable Non-local Spin Control in a Coupled Quantum Dot System
• Non-zero temperature transport near quantum critical points
• NRG study of the Kondo effect in the presence of itinerant-electron ferromagnetism
• Overscreened multi-channel SU(N) Kondo model : large-N solution and Conformal Field Theory
• Kondo effect in a quantum dot coupled to ferromagnetic leads: A numerical renormalization group analysis
• Detection of Quantum Noise from an Electrically-Driven Two-Level System
• Quantum phase transitions in the sub-ohmic spin-boson model: Failure of the quantum-classical mapping
• Kondo resonances and anomalous gate dependence of electronic conduction in single-molecule transistors
• Critical local moment fluctuations in the Bose-Fermi Kondo model
• Spin-Flavor Separation and Non-Fermi Liquid Behavior in the Multichannel Kondo Problem: A Large N Approach
• Quantum phase transitions in the Bose-Fermi Kondo model
• Quantum phase transition in a two-channel-Kondo quantum dot device
• Quantum critical properties of the Bose-Fermi Kondo Model in a large-N limit
• Numerical renormalization-group study of the Bose-Fermi Kondo model
• Interaction of a Magnetic Impurity with Strongly Correlated Conduction Electrons
• Frequency-dependent transport through a quantum dot in the Kondo regime
• Singular Effects of Impurities near the Ferromagnetic Quantum-Critical Point
• The pseudogap Fermi-Bose Kondo model
• Destruction of the Kondo effect in a multi-channel Bose-Fermi Kondo model

Cited by in corpus (27)

• Heavy-electron quantum criticality and single-particle spectroscopy
• Critical and strong-coupling phases in one- and two-bath spin-boson models
• Kondo physics and dissipation: A numerical renormalization-group approach to Bose-Fermi Kondo models
• Universality and the zero-bias conductance of the single-electron transistor
• Universal zero-bias conductance for the single electron transistor. II: Comparison with numerical results
• Quantum Criticality out of Equilibrium: Steady State in a Magnetic Single-Electron Transistor
• Scaling and Enhanced Symmetry at the Quantum Critical Point of the Sub-Ohmic Bose-Fermi Kondo Model
• Spin Path Integrals, Berry phase, and the Quantum Phase Transition in the sub-Ohmic Spin-boson Model
• Quantum criticality in the pseudogap Bose-Fermi Anderson and Kondo models: Interplay between fermion- and boson-induced Kondo destruction
• Observation of Kondo condensation in a degenerately doped silicon metal
• Underscreened Kondo effect in quantum dots coupled to ferromagnetic leads
• Dynamical scaling of charge and spin responses at a Kondo destruction quantum critical point
• Local quantum criticality out of equilibrium - effective temperatures and scaling in the steady state regime
• Quantum phase transitions in a resonant-level model with dissipation: Renormalization-group studies
• Quantum phase transitions in a charge-coupled Bose-Fermi Anderson model
• The Functional Integral formulation of the Schrieffer-Wolff transformation
• Entanglement Entropy Near Kondo-Destruction Quantum Critical Points
• On the concept of effective temperature in current carrying quantum critical states
• Mixed-order symmetry-breaking quantum phase transition far from equilibrium
• Impurity resonant state in d-wave superconductors: in favor of a Kondo-like response
• Bose-Fermi Kondo model with Ising anisotropy: cluster-Monte Carlo approach
• Quantum Chaos of the Bose-Fermi Kondo model at the intermediate temperature
• Quantum criticality out of equilibrium in the pseudogap Kondo model
• Magnetic Single-Electron Transistor as a Tunable Model System for Kondo-Destroying Quantum Criticality
• Quantum criticality in the spin-isotropic pseudogap Bose-Fermi Kondo model: entropy, scaling, and the g-theorem
• Controlled Electrode Magnetization Alignment in Planar Elliptical Ferromagnetic Break Junction Devices
• Residual Kondo effect in quantum dot coupled to half-metallic ferromagnets