June 16, 2024

Star Attraction: Magnetism Generated by Star-Like Kagome Geometry Arrangement of Molecules

By ARC Centre of Quality in Future Low-Energy Electronic Devices Technologies
September 15, 2021

The star-like kagome molecular structure of the 2D metal-organic material results in strong electronic interactions and non-trivial magnetic residential or commercial properties (left: STM image, right: non-contact AFM). Credit: FLEET

2D kagome materials are a platform for tuneable electron-electron interactions
Star-like atomic-scale kagome geometry changes on magnetism in a 2D natural product

The local magnetism is the effect of electron-electron interactions within the 2D star-arranged metal-organic assembly.” The Kondo impact is a many-body phenomenon that takes place when magnetic minutes are evaluated by a sea of conduction electrons. Theoretical modeling by Bernard Field and associates unambiguously showed that this magnetism is the direct repercussion of strong Coulomb interactions between electrons. These interactions appear just when we bring the usually non-magnetic parts into a 2D kagome metal-organic framework. These interactions hinder electron pairing, with spins of unpaired electrons giving increase to regional magnetic moments.

A 2D nanomaterial consisting of natural particles connected to metal atoms in a specific atomic-scale geometry reveals non-trivial electronic and magnetic residential or commercial properties due to strong interactions between its electrons.
A new study, released today, shows the development of magnetism in a 2D natural product due to strong electron-electron interactions; these interactions are the direct consequence of the materials unique, star-like atomic-scale structure.
This is the very first observation of local magnetic moments emerging from interactions between electrons in an atomically thin 2D organic product

The findings have potential for applications in next-generation electronic devices based upon organic nanomaterials, where tuning of interactions between electrons can result in a vast series of magnetic and electronic phases and properties.
Strong electron-electron Interactions in a 2D natural kagome product.
The Monash University research study investigated a 2D metal-organic nanomaterial composed of organic particles set up in a kagome geometry, that is, following a star-like pattern.
” Where does the local magnetism originated from?” Lead author Dr Dhaneesh Kumar asked and addressed this key concern. The local magnetism is the effect of electron-electron interactions within the 2D star-arranged metal-organic assembly. Credit: FLEET
The 2D metal-organic nanomaterial includes dicyanoanthracene (DCA) molecules collaborated with copper atoms on a weakly-interacting metal surface (silver).
By methods of atomically accurate and mindful scanning probe microscopy (SPM) measurements, the scientists found that the 2D metal-organic structure– whose molecular and atomic structure blocks are on their own non-magnetic– hosts magnetic minutes confined at particular locations.
Theoretical estimations revealed that this emergent magnetism is due to strong electron-electron Coulomb repulsion offered by the particular 2D kagome geometry.
” We believe that this can be crucial for the development of future electronics and spintronics technologies based on natural materials, where tuning of interactions between electrons can result in manage over a vast array of electronic and magnetic homes,” says FLEET CI A/Prof Agustin Schiffrin.
Direct penetrating of magnetism via the Kondo effect
The electrons of 2D materials with a kagome crystal structure can be based on strong Coulomb interactions due to devastating wavefunction interference and quantum localisation, leading to a large range of topological and strongly associated electronic stages.
Such strong electronic connections can manifest themselves by means of the development of magnetism, and, till now, have not been observed in atomically-thin 2D organic products. The latter can be advantageous for solid-state innovations owing to their tunability and self-assembly ability.
In this study, magnetism resulting from strong electron-electron Coulomb interactions in a 2D kagome organic product was revealed through the observation of the Kondo impact.
” The Kondo result is a many-body phenomenon that takes place when magnetic minutes are screened by a sea of conduction electrons. From an underlying metal,” states lead author and FLEET member Dr Dhaneesh Kumar. “And this result can be discovered by SPM methods.”
” We observed the Kondo impact, and from there concluded that the 2D organic product should host magnetic minutes. The question then ended up being where does this magnetism come from?”.
Theoretical modeling by Bernard Field and colleagues unambiguously showed that this magnetism is the direct effect of strong Coulomb interactions in between electrons. When we bring the normally non-magnetic parts into a 2D kagome metal-organic framework, these interactions appear only. These interactions prevent electron pairing, with spins of unpaired electrons generating local magnetic moments.
” Theoretical modeling in this research study offers an unique insight into the richness of the interaction between quantum correlations, and the topological and magnetic stages. The research study provides us with a few hints on how these non-trivial phases can be managed in 2D kagome products for prospective applications in path-breaking electronic devices technologies,” states FLEET CI A/Prof Nikhil Medhekar.
The study.
Referral: “Manifestation of Strongly Correlated Electrons in a 2D Kagome Metal-Organic Framework” by Dhaneesh Kumar, Jack Hellerstedt, Bernard Field, Benjamin Lowe, Yuefeng Yin, Nikhil V. Medhekar and Agustin Schiffrin, 12 September 2021, Advanced Functional Materials.DOI: 10.1002/ adfm.202106474.
The research team consisted of FLEET experimentalists and theoreticians from Monash Universitys School of Physics & & Astronomy and Department of Materials Science & & Engineering.
All experiments were carried out at Monash University, supported through the Australian Research Council (Centre of Excellence and Future Fellowship programs). Mathematical estimations performed at Monash were supported by resources offered by the National Computing Infrastructure (NCI) and Pawsey Supercomputing Centre. Further assistance was gotten from the Australian Governments Research Training Program.
Scanning probe microscopy (SPM) at FLEET.
A/Prof Schiffrins group at FLEET uses SPM to investigate the atomic-scale properties– electronic and structural– of brand-new nanomaterials with capacity for future low-energy electronic technologies.
First principles theory research studies at FLEET.
A/Prof Medhekars group at FLEET utilizes atomistic modeling methods based on first principles to investigate links between atomic-level structure and electronic properties of a broad range nanomaterials, including the low-dimensional products that are assuring for the next-generation electronics innovations.
FLEET is an Australian Research Council-funded research study center combining over a hundred International and australian experts to establish a brand-new generation of ultra-low energy electronics.