【摘 要】
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The Kondo effect,a many-body phenomenon arising from screening a magnetic impurity by itinerant electrons,has fascinated physicist since its discovery.This presentation demonstrates a system applying
【机 构】
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Department of Physics,The Hong Kong University of Science and Technology,Hong Kong,China
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The Kondo effect,a many-body phenomenon arising from screening a magnetic impurity by itinerant electrons,has fascinated physicist since its discovery.This presentation demonstrates a system applying supramolecular assembly to control the adsorption configuration of Co-porphyrin molecules on Au(111)and Cu(111)surfaces.By means of cryogenic scanning tunneling microscopy,the Kondo effect associated with the Co center is revealed absent or present in different supramolecular systems.To study this switching behavior,we perform first-principles calculations to obtain spin-polarized electronic structures and compute the Kondo temperatures using the Anderson impurity model.The switching behavior is traced to varied molecular adsorption heights in different supramolecular structures.These findings unravel that a competition between intermolecular interactions and molecule–substrate interactions subtly regulates the molecular Kondo effect in supramolecular systems.
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