J. Lagoute | Searcharxiv

arXiv2024

Spin-Wave-Assisted Thermal Reversal of Epitaxial Perpendicular Magnetic Nanodots

The magnetic susceptibility of self-organized two-dimensional Co nanodots on Au(111) has been measured as a function of their size in the 2-7~nm diameter range. We show that the activation energy for the thermal reversal displays a power law behavior with the dot volume. Atomic scale simulations based on the Heisenberg hamiltonian show that this behavior is due to a deviation from the macrospin model for dot size as small as 3~nm in diameter. This discrepancy is attributed to finite temperature effects through the thermal excitation of spin-wave modes inside the particles

cond-mat.mes-hall↗

arXiv2006

Molecular Self-Assembly of Jointed Molecules on a Metallic Substrate: From Single Molecule to Monolayer

Because of its promising contribution to the bottom-up approach for nanofabrication of complex molecular architectures, self-organization is widely studied nowadays. Numerous studies have tackled supramolecular chirality or low-dimensional molecular nanostructures using in most cases small and rigid molecules adsorbed on metallic substrates. In this situation, self-assembled structures can be understood in relative simple terms considering molecule-molecule versus molecule-substrate interactions. In contrast, the case of large and three-dimensional molecules which can adopt different adsorption conformations is more complex. Here, we investigate the self-assembly of V-Landers molecules (C108H104) on Cu(100) by STM at room temperature under ultrahigh vacuum. This molecule is constituted of a central poly-aromatic board linked by sigma bonds to four 3,5-di-tert-butylphenyl legs.

cond-mat.mtrl-sci↗