Wiedemann-Franz law in a non-Fermi liquid and Majorana central charge: Thermoelectric transport in a two-channel Kondo system

Abstract

Quantum dot devices allow one to access the critical point of the two-channel Kondo model. The effective critical theory involves a free Majorana fermion quasiparticle localized on the dot. As a consequence, this critical point shows both the phenomenon of non-Fermi liquid physics and fractionalization. Although a violation of the Wiedemann-Franz law is considered a defining feature of non-Fermi liquid systems, we show by exact calculations that it holds at the critical point, providing a counterexample to this lore. Furthermore, we show that the fractionalized Majorana character of the critical point can be unambiguously detected from the heat conductivity, opening the door to a direct experimental measurement of the elusive Majorana central charge $c=\frac{1}{2}$.

18 pages, 3 figures

References in corpus (14)

• The numerical renormalization group method for quantum impurity systems
• Observation of the two-channel Kondo effect
• Sum-rule Conserving Spectral Functions from the Numerical Renormalization Group
• Kondo effect in quantum dots
• Thermopower of a Kondo-correlated quantum dot
• Thermoelectric transport through strongly correlated quantum dots
• Violation of the Wiedemann-Franz Law in a Single-Electron Transistor
• Quantum phase transition in a two-channel-Kondo quantum dot device
• Universal low-temperature crossover in two-channel Kondo models
• Large violation of Wiedemann Franz law in Luttinger liquids
• Anyons in Multichannel Kondo Systems
• Thermoelectric Transport in a Three-Channel Charge Kondo Circuit
• Transport Signatures of Majorana Quantum Criticality Realized by Dissipative Resonant Tunneling
• Quantum Criticality in Resonant Andreev Conduction

Cited by in corpus (15)

• Fractional entropy of multichannel Kondo systems from conductance-charge relations
• Violation of the Wiedemann-Franz law in the Topological Kondo model
• Thermoelectric Transport in a Three-Channel Charge Kondo Circuit
• SO(5) non-Fermi liquid in a Coulomb box device
• Manipulating Non-Abelian Anyons in a Chiral Multichannel Kondo Model
• Generalized Wiedemann-Franz law in a two-site charge Kondo circuit: Lorenz ratio as a manifestation of the orthogonality catastrophe
• Coulomb blockade oscillations of heat conductance in the charge Kondo regime
• Quantum thermoelectric and heat transport in the overscreened Kondo regime: Exact conformal field theory results
• Wiedemann-Franz law in scattering theory revisited
• SO(5) critical point in a spin-flavor Kondo device -- Bosonization and refermionization solution
• Thermoelectric transport across a tunnel contact between two charge Kondo circuits: beyond perturbation theory
• Chiral numerical renormalization group
• Electric and heat transport in a charge two-channel Kondo device
• Universal relations between thermoelectrics and noise in mesoscopic transport across a tunnel junction
• Noise signatures of a charged Sachdev-Ye-Kitaev dot in mesoscopic transport