PhD Thesis Defense | Andrea Aguirre
CFM Seminars
- Speaker
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Andrea Aguirre
CFM and CIC nanoGUNE - When
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2025/01/24
11:00 - Place
- CFM Auditorium
- Host
- Martina Corso and Nacho Pascual
- Add to calendar
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iCal
Two-Dimensional Magnetism and Molecular Interaction in Transition Metal Dihalides
Candidate: Andrea Aguirre
Supervisors: Martina Corso and Nacho Pascual
Summary
Transition metal dihalides (TMDHs) are 2D layered materials with magnetic and semiconducting properties, making them promising candidates for various applications. This study explored the growth and characterization of FeCl₂, NiCl₂, CoCl₂, and CoBr₂ using techniques like X-ray absorption spectroscopy (XAS), scanning tunneling microscopy (STM), and X-ray photoelectron spectroscopy (XPS). Findings revealed that TMDHs retain their magnetic order even at the monolayer level, enabling the creation of molecule-TMDH heterostructures for magnetoelectric devices. Additionally, investigations into their interactions with molecules highlighted their potential for organic-inorganic hybrid materials, such as MnPc/CoBr₂ heterojunctions with strong antiferromagnetic coupling. Further, the synthesis of organometallic 2D structures, including chiral graphene nanoribbons (ch-GNR) with iron cations, demonstrated stability in air, suggesting applications in electronic and sensing devices.
[caption id="attachment_63083" align="aligncenter" width="600"]
Local magnetic order probed by NiCp2 IETS experiment on FeCl2 and NiCl2. a-d) Second derivative conductance map as a function of the tip-surface distance taken on FeCl2 (a) and NiCl2 (b) without applied external magnetic field, and c-d) under 3 T of external magnetic field. The curves were smoothed to reduce the noise. e) On top, d2I/dV2 map as a function of the magnetic field, ramping in 0.1 T steps from -1 T to 1 T. Below, a comparison between the absolute value of magnetization with respect to the external magnetic field (NI), and the absolute value of the splitting of the IETS peaks of the NiCp2. The shadowed part in grey indicates the saturating point of the magnetization value. The dashed line indicates the onset of magnetization at 0.65 T. A sketch of the behavior of NiCl2 under the external magnetic field is shown at the bottom.[/caption]