Spin dependent transmission of Nickelocene-Cu contacts probed with shot noise

Abstract

The current $I$ through nickelocene molecules and its noise are measured with a low temperature scanning tunneling microscope on a Cu(100) substrate. Density functional theory calculations and many-body modeling are used to analyze the data. During contact formation, two types of current evolution are observed, an abrupt jump to contact and a smooth transition. These data along with conductance spectra ($dI/dV$) recorded deep in the contact range are interpreted in terms of a transition from a spin-1 to a spin-1/2 state that is Kondo screened. Many-body calculations show that the smooth transition is also consistent with a renormalization of spin excitations of a spin-1 molecule by Kondo exchange coupling. The shot noise is significantly reduced compared to the Schottky value of $2eI$ but no influence of the Kondo effect or spin excitations are resolved. The noise can be described in the Landauer picture in terms of spin-polarized transmission of $\approx$35% through two degenerate $d_{\pi }$-orbitals of the Nickelocene molecule.

10 pages, 10 figures; revised version published in Phys. Rev. B

References in corpus (11)

• Improvements on non-equilibrium and transport Green function techniques: the next-generation transiesta
• Highly conductive molecular junctions based on direct binding of benzene to platinum electrodes
• Electron-vibration interaction in single-molecule junctions: from contact to tunneling regime
• Passing current through touching molecules
• Properties of anisotropic magnetic impurities on surfaces
• Probing Magnetic Excitations and Correlations in Single and Coupled Spin Systems with Scanning Tunneling Spectroscopy
• Excitation of local magnetic moments by tunnelling electrons
• Electrically addressing the spin of a magnetic porphyrin through covalently connected graphene electrodes
• Current noise through a Kondo quantum dot in a SU(N) Fermi liquid state
• Shot Noise in SU(N) Quantum Dot Kondo Effects
• Conductance channels of a platform molecule on Au(111) probed with shot noise

Cited by in corpus (1)

• Current shot noise in atomic contacts: Fe and FeH${}_2$ between Au electrodes