title: Ensemble Control of Kondo Screening in Molecular Adsorbates.
abstract: Switching the magnetic properties of organic semiconductors on a metal surface has thus far largely been limited to molecule-by-molecule tip-induced transformations in scanned probe experiments. Here we demonstrate with molecular resolution that collective control of activated Kondo screening can be achieved in thin-films of the organic semiconductor titanyl phthalocyanine on Cu(110) to obtain tunable concentrations of Kondo impurities. Using low-temperature scanning tunneling microscopy and spectroscopy, we show that a thermally activated molecular distortion dramatically shifts surface-molecule coupling and enables ensemble-level control of Kondo screening in the interfacial spin system. This is accompanied by the formation of a temperature-dependent Abrikosov-Suhl-Kondo resonance in the local density of states of the activated molecules. This enables coverage-dependent control over activation to the Kondo screening state. Our study thus advances the versatility of molecular switching for Kondo physics and opens new avenues for scalable bottom-up tailoring of the electronic structure and magnetic texture of organic semiconductor interfaces at the nanoscale.
authors.affiliation: University of Arizona , Department of Chemistry & Biochemistry, 1306 East University Boulevard, Tucson, Arizona 85721, United States.
authors.forename: Bret
authors.identifier: http://orcid.org/0000-0003-2984-0225
authors.initials: B
authors.lastname: Maughan
authors.affiliation: Brookhaven National Laboratory , Center for Functional Nanomaterials, Upton, New York 11973, United States.
authors.forename: Percy
authors.initials: P
authors.lastname: Zahl
authors.affiliation: Brookhaven National Laboratory , Center for Functional Nanomaterials, Upton, New York 11973, United States.|Department of Electrical & Computer Engineering, University of Nebraska-Lincoln , Lincoln, Nebraska 68588, United States.
authors.forename: Peter
authors.initials: P
authors.lastname: Sutter
authors.affiliation: University of Arizona , Department of Chemistry & Biochemistry, 1306 East University Boulevard, Tucson, Arizona 85721, United States.|University of Arizona , Department of Physics, 1118 East Fourth Street, Tucson, Arizona 85721, United States.
authors.forename: Oliver L A
authors.identifier: http://orcid.org/0000-0002-0974-7253
authors.initials: OLA
authors.lastname: Monti