Ferromagnetism on an atom-thick & extended 2D metal-organic coordination network
Jorge Lobo-Checa1,2, Leyre Hernández-López3,4, Mikhail M Otrokov5,6,7,8
1Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, 50009, Zaragoza, Spain. jorge.lobo@csic.es.
Nature Communications
|February 29, 2024
Summary
Researchers achieved two-dimensional ferromagnetism in an atomically thin metal-organic coordination network. This breakthrough, observed in a material with low iron content, exhibits robust magnetic properties up to 35 K.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Ferromagnetism, characterized by spontaneous magnetic alignment below the Curie temperature, is a fundamental property of magnetic materials.
- Achieving two-dimensional (2D) ferromagnetism in metal-organic coordination networks has been a long-standing challenge, with previous attempts eluding experimental success.
Purpose of the Study:
- To experimentally demonstrate the feasibility of extended, cooperative ferromagnetism in an atomically thin 2D metal-organic coordination network.
- To characterize the magnetic properties and understand the underlying mechanisms of ferromagnetism in this novel 2D material.
Main Methods:
- Fabrication of an atomically thin 2D metal-organic coordination network.
- Characterization of magnetic properties, including hysteresis loops, coercive fields, and magnetic anisotropy.
- Determination of the Curie temperature (TC) and investigation of exchange interactions.
Main Results:
- Successful realization of cooperative ferromagnetism in a 2D metal-organic coordination network, with only approximately 5% Fe atoms in the monolayer.
- Observed an out-of-plane easy-axis square-like hysteresis loop with high coercive fields (> 2 Tesla) and significant magnetic anisotropy.
- Ferromagnetic state persists up to a Curie temperature of approximately 35 K, driven by molecular linker-mediated exchange interactions.
Conclusions:
- This study provides the first experimental evidence of ferromagnetism in 2D metal-organic coordination networks, resolving a two-decade search.
- The findings highlight the potential of engineered 2D materials for spintronic applications, even with dilute magnetic elements.
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