Inverse Isotope Effect on Kondo Temperature in Electron-Rattling System

Abstract

In an electron system coupled with anharmonic phonons, i.e., {\it rattling}, inverse isotope effect on the Kondo temperature $T_{\mathrm{K}}$ is found to occur by the numerical evaluation of the Sommerfeld constant $\gamma$ of the Anderson-Holstein model. For the anharmonic potential of an oscillator with mass $M$ in which large $\gamma$ has been found to be almost independent of an applied magnetic field, $\gamma$ is significantly suppressed when $M$ is increased, i.e., $T_{\mathrm{K}}$ is enhanced due to the relation of $\gamma$$\sim$$T_{\mathrm{K}}^{-1}$ in the Kondo problem, leading to the inverse isotope effect on $T_{\mathrm{K}}$. Since this phenomenon does not occur for harmonic phonons, it can be a key experiment to prove the relevance of rattling to magnetically robust heavy electron state.

4 pages, 3 figures. To appear in J. Phys. Soc. Jpn

References in corpus (7)

• Exotic Heavy-Fermion State in Filled Skutterudite SmOs4Sb12
• Time-dependent Density-Matrix Renormalization-Group Methods
• Local Heavy Quasiparticle in Four-Level Kondo Model
• Phonon softening and double-well potential formation due to electron-phonon interaction in heavy-fermion systems
• Effect of Rattling Phonons on Sommerfeld Constant
• Enhanced Kondo Effect in an Electron System Dynamically Coupled with Local Optical Phonon
• Realization of Strong Coupling Fixed Point in Multilevel Kondo Models

Cited by in corpus (9)

• Strong-Coupling Theory of Rattling-Induced Superconductivity
• Electron Mass Enhancement due to Anharmonic Local Phonons
• Bipolaron-SO(5) Non-Fermi Liquid in a Two-channel Anderson Model with Phonon-assisted Hybridizations
• Heavy-Electron Formation and Bipolaronic Transition in the Anharmonic Holstein Model
• Electric Dipolar Susceptibility of the Anderson-Holstein Model
• Kondo Effect of a Jahn-Teller Ion Vibrating in a Cubic Anharmonic Potential
• Chaos in Jahn-Teller Rattling
• Crystalline Electric Field and Kondo Effect in SmOs4Sb12
• Anomalous Isotope Effect in Rattling-Induced Superconductor