Conductivity Enhancement in a Diffusive Fermi Liquid due to Bose-Einstein Condensation of Magnons

Abstract

We theoretically study the conductivity of a disordered 2D metal when it is coupled to ferromagnetic magnons with a quadratic spectrum and a gap $\Delta$. In the diffusive limit, a combination of disorder and magnon-mediated electron interaction leads to a sharp metallic correction to the Drude conductivity as the magnons approach criticality, i.e., $\Delta \to 0$. The correction is non-singular and is distinctively weaker than, for example, the logsquared correction obtained when disordered electrons couple to diffusive spin fluctuations near a Hertz-Millis transition. The possibility of verifying this prediction in an S = 1/2 easy-plane ferromagnetic insulator K${}_2$CuF${}_4$ under an external magnetic field is proposed. Our results show that the onset of a magnon BEC in an insulator can be detected via electrical transport measurements on the proximate metal.

arXiv commentFive pages with four figures

References in corpus (21)

• Spin Hall Magnetoresistance Induced by a Non-Equilibrium Proximity Effect
• Theory of spin Hall magnetoresistance
• Bose-Einstein Condensation in Magnetic Insulators
• Realization of Bose-Einstein condensation of dilute magnons in TlCuCl${}_3$
• Quantitative study of the spin Hall magnetoresistance in ferromagnetic insulator/normal metal hybrids
• Interaction corrections at intermediate temperatures: I. Longitudinal conductivity and kinetic equation
• Interplay of disorder and spin fluctuations in the resistivity near a quantum critical point
• Spin Hall magnetoresistance in antiferromagnet/heavy-metal heterostructures
• Spin Insulatronics
• Tunable sign change of spin Hall magnetoresistance in Pt/NiO/YIG structures
• Spin Hall Magnetoresistance in a Canted Ferrimagnet
• Spin-Hall magnetoresistance and spin Seebeck effect in spin-spiral and paramagnetic phases of multiferroic CoCr2O4 films
• Amperean Pairing at the Surface of Topological Insulators
• Superconductivity Induced by Interfacial Coupling to Magnons
• Superconductivity at metal-antiferromagnetic insulator interfaces
• On the residual resistivity near a two dimensional metamagnetic quantum critical point
• Quantum Correction to Conductivity Close to Ferromagnetic Quantum Critical Point in Two Dimensions
• Transport Anomalies and Marginal Fermi-Liquid Effects at a Quantum Critical Point
• Quasi-two-dimensional Bose-Einstein condensation of lattice bosons in spin-1/2 XXZ ferromagnet K${}_2$CuF${}_4$
• Conductivity close to antiferromagnetic criticality
• Interaction Correction of Conductivity Near a Ferromagnetic Quantum Critical Point

Cited by in corpus (2)

• The Condensation of Ideal Dunkl-Bose Gas in Power-Law Traps
• Ferroelectricity in a magnon Bose-Einstein condensate: Nonreciprocal superfluidity, exceptional points, and Majorana bosons