Benjamin Lowe, Monash
Controlling interactions between two-dimensional (2D) materials and their substrate is critical if the properties of these materials are to be exploited in new technologies. One of the most dramatic examples of the influence of a substrate is the Kondo effect, in which local magnetic moments are screened by conduction electrons of a host metal.
Here, we synthesise a 2D kagome metal-organic framework (MOF) consisting of 9,10-dicyanoanthracene (DCA) molecules coordinated to copper atoms on a silver surface, Ag(111). Via scanning tunnelling spectroscopy (STS), we observe a zero-bias peak indicative of the Kondo effect as confirmed by temperature-dependent measurements.
This feature indicates the presence of local magnetic moments in the MOF which are the result of strong electron correlations. We are able to control the strength of the many-body Kondo screening by using a scanning tunnelling microscope tip to manipulate the MOF, changing both the MOF-Ag(111) adsorption height and resulting Kondo screening strength.
This protocol is a means of controlling exchange coupling with atomic-scale precision and without the need for a magnetic field, making it potentially applicable for spintronics applications.
About the presenter
Benjamin Lowe is a PhD student at Monash University where he works in Research theme 1 with A/Prof Agustin Schiffrin studying the self-assembly of metal-organic systems using a state-of-the-art scanning probe microscopy (SPM)facility that allows metal-organic systems to be engineered and probed with atomic-scale precision. He seeks to develop systems with electronic and opto-electronic properties that are of interest both fundamentally and for prospective electronics applications.