Jungiusstr. 11, Hörsaal AP
SFB 668 - Kolloquium
Dr. Ph. Sainctavit (SLS and Soleil, France):
Magnetic memory of a single-molecule quantum magnet wired to a gold surface
In the field of molecular spintronics the use of magnetic molecules for information technology is a main target and the observation of magnetic hysteresis on individual molecules organized on surfaces is a necessary step to develop molecular memory arrays. Information storage at the molecular level requires molecules exhibiting an intrinsic remnant magnetization, like the so-called single-molecule magnets (SMMs). These have been intensively investigated for their rich quantum behaviour but no magnetic hysteresis had been so far reported for monolayers of SMMs on various non-magnetic substrates, most probably owing to the chemical instability of clusters on surfaces. Using X-ray absorption spectroscopy and X-ray magnetic circular dichroism synchrotron-based techniques, pushed to the limits in sensitivity and operated at sub-kelvin temperatures (400 mK), we have now found that robust, tailor-made Fe4 complexes retain magnetic hysteresis at gold surfaces [4,5,6]. Our results demonstrate that isolated SMMs can be used for storing information. The road is now open to address individual molecules wired to a conducting surface in their blocked magnetization state, thereby enabling investigation of the elementary interactions between electron transport and magnetism degrees of freedom at the molecular scale.
 R. Sessoli et al. Nature 365, 141?143 (1993).
 D. Gatteschi et al. Molecular Nanomagnets (Oxford Univ. Press, 2006).
 M. Mannini, Ph. Sainctavit et al. Chemistry : a European Journal 14, 7530?7535 (2008).
 M. Mannini, F. Pineider, Ph. Sainctavit et al. Nature Materials 8, 194?197 (2009).
 M. Mannini, F. Pineider, Ph. Sainctavit et al. Advanced Materials 21, 167?171 (2009).
 M. Mannini, F. Pineider, Ph. Sainctavit et al. Nature 468, 417?421 (2010).