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arXiv · 1204.1108

Dynamical magnetic anisotropy and quantum phase transitions in a vibrating spin-1 molecular junction

David A. Ruiz-Tijerina·Pablo S. Cornaglia·C. A. Balseiro·Sergio E. Ulloa
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Abstract

We study the electronic transport through a spin-1 molecule in which mechanical stretching produces a magnetic anisotropy. In this type of device, a vibron mode along the stretching axis will couple naturally to the molecular spin. We consider a single molecular vibrational mode and find that the electron-vibron interaction induces an effective correction to the magnetic anisotropy that shifts the ground state of the device toward a non-Fermi liquid phase. A transition into a Fermi liquid phase could then be achieved, by means of mechanical stretching, passing through an underscreened spin-1 Kondo regime. We present numerical renormalization group results for the differential conductance, the spectral density, and the magnetic susceptibility across the transition.

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David A. Ruiz-Tijerina, Pablo S. Cornaglia, C. A. Balseiro, Sergio E. Ulloa. 2012-04-05. Dynamical magnetic anisotropy and quantum phase transitions in a vibrating spin-1 molecular junction. https://doi.org/10.1103/physrevb.86.035437

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