COLL 406 |
| Magnetic nanostructures are increasing data storage capacities and are promising candidates for implementations of novel spin-based computation techniques. The relative simplicity and reduced dimensionality of nanoscale magnetic structures such as molecular magnets also make them attractive model systems for studying the interactions between small numbers of quantum spins. Using a high-field low-temperature scanning tunneling microscope, we assembled linear chains of Mn atoms one atom at a time on thin, insulating layers of copper nitride. We probed the excitation spectra of the individual magnetically-coupled chains with inelastic electron tunneling spectroscopy. The spectra changed dramatically with both the parity and length of the chain and revealed a variety of spin excitations. These results provide direct evidence of antiferromagnetic coupling between the atomic spins on neighboring Mn atoms. A quantitative comparison with the Heisenberg open chain model allows us to measure the coupling strength ~6meV between these atomic spins. |
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Dynamics of Single Atoms, Molecules and Clusters on Surfaces
2:00 PM-5:30 PM, Tuesday, 12 September 2006 Sir Francis Drake -- Renaissance Room, Oral
Division of Colloid & Surface Chemistry |