Digital.CSIC. Repositorio Institucional del CSIC

oai:digital.csic.es:10261/336588

Colección de datos originales necesarios para la elaboración del artículo al que hace referencia el título. Incluye imágenes en formato binario *.sxm, datos ascii enformato *.txt o *.dat, archivos de origin *.opj, e imágenes *.bmp, Low dimensional carbon-based materials can show intrinsic magnetism associated to p-electrons in open-shell $\pi$-conjugated systems. Chemical design provides atomically precise control of the $\pi$-electron cloud, which makes them promising for nanoscale magnetic devices. However, direct verification of their spatially resolved spin-moment remains elusive. Here, we report the spin-polarization of chiral graphene nanoribbons (one-dimensional strips of graphene with alternating zig-zag and arm-chair boundaries), obtained by means of spin-polarized scanning tunnelling microscopy. We extract the energy-dependent spin-moment distribution of spatially extended edge states with $\pi$-orbital character, thus beyond localized magnetic moments at radical or defective carbon sites. Guided by mean field Hubbard calculations, we demonstrate that electron correlations are responsible for the spin-splitting of the electronic structure. Our versatile platform utilizes a ferromagnetic substrate that stabilizes the organic magnetic moments against thermal and quantum fluctuations, while being fully compatible with on-surface synthesis of the rapidly growing class of nanographenes., We acknowledge financial support from the Spanish Ministry of Science and Innovation MICIN through grant nos. PID2019-107338RB-C64, PID2019-107338RB-C61, PID2019-107338RB-C62, PID2019-107338RB-C63, PID2020–115406GB-I00 funded by AEI/10.13039/501100011033; grant no. PCI2019-111933-2; and red tem\'{a}tica RED2018-102833-T. This work was also supported by European Regional Development Fund (ERDF) under the program Interreg V-A España-Francia-Andorra (grant no. EFA194/16 TNSI), the European Union (EU) H2020 program through the FET-Open project SPRING (Grant Agreement No. 863098), the Maria de Maeztu Units of Excellence Program CEX2020-001038-M, the Aragon Government (E13-20R and E12-20R), the Programa Red Guipuzcoana de Ciencia, Tecnología e Innovación 2021 (Grant No. 2021-CIEN-000069-01. Gipuzkoa Next), the Basque Departmente of Educatioon (PRE-2021-2-0190 and PIBA-2020-1-0014), and the Xunta de Galicia (Centro de Investigación accreditation 2019–2022, ED431G2019/03), Peer reviewed