Kondo effect of an adsorbed cobalt phthalocyanine (CoPc) molecule: the role of quantum interference

Abstract

A recent experimental study showed that, distorting a CoPc molecule adsorbed on a Au(111) surface, a Kondo effect is induced with a temperature higher than 200 K. We examine a model in which an atom with strong Coulomb repulsion (Co) is surrounded by four atoms on a square (molecule lobes), and two atoms above and below it representing the apex of the STM tip and an atom on the gold surface (all with a single, half-filled, atomic orbital). The Hamiltonian is solved exactly for the isolated cluster, and, after connecting the leads (STM tip and gold), the conductance is calculated by standard techniques. Quantum interference prevents the existence of the Kondo effect when the orbitals on the square do not interact (undistorted molecule); the Kondo resonance shows up after switching on that interaction. The weight of the Kondo resonance is controlled by the interplay of couplings to the STM tip and the gold surface, and between the molecule lobes.

5 pages, 3 figuras

References in corpus (3)

• Many Body Effects on the Transport Properties of Single-Molecule Devices
• Interference Effects on Kondo-Assisted Transport through Double Quantum Dots
• STM conductance of Kondo impurities on open and structured surfaces

Cited by in corpus (6)

• Many-body electronic structure and Kondo properties of cobalt-porphyrin molecules
• A Novel Approach to Study Highly Correlated Nanostructures: The Logarithmic Discretization Embedded Cluster Approximation
• Kondo effect in transport through molecules adsorbed on metal surfaces: from Fano dips to Kondo peaks
• Spin-Polarized STM for a Kondo adatom
• Slave boson theory for transport through magnetic molecules with vibronic states
• Scanning tunneling microscopy of adsorbed molecules on metalic surfaces for nearly localized atomic states