Final Activity Report Summary - QUEMOLNA (Quantum Effects in Molecular Nanomagnets)
The first goal of a research training network (RTN) is that of training experienced researchers (ER) and early-stage researchers (ESR) so as to make them competitive and qualified within the job market. Quantitative data clearly indicated that QUEMOLNA reached this goal. Out of the 27 persons hired by the RTN, five got permanent positions in academia, four were hired by industries, seven were engaged as post-doctoral researchers by other European laboratories and several were finishing the PhD thesis initiated by using the RTN grants by the time of the project completion. The interdisciplinary nature of the training which was provided by QUEMOLNA was one of the reasons of its success.
QUEMOLNA was also successful in terms of the development of the European research area (ERA), acting as catalyst for the initiation of a NoE, MAGMANet, where the RTN themes were developed. The use of magnetic molecules (MM) for quantum computing was developed in a SMALL project, approved by the Seventh Framework Programme.
The scientific output of QUEMOLNA was very high, both in terms of quantity and quality of scientific publications. The high degree of integration was demonstrated by over 200 papers which were jointly produced by two or more RTN units.
The stated goal of QUEMOLNA was that of investigating quantum effects in molecular nanomagnets, i.e. molecular systems which fell in the intermediate region between the one in which classic descriptions of magnetism worked and that in which quantum effects dominated. MM were investigated in order to understand quantum matter, opening exciting perspectives, e.g. for new types of magnetic memories using both classic and quantum approaches, such as quantum computing. In short, the goal was that of developing the so-called molecular spintronics. A key point to achieve success was the interdisciplinary team of groups which collaborated, with backgrounds as diverse as synthetic chemists, specialists in nanofabrication and solid state physicists with background in experimental techniques and theory.
The control of molecular design allowed for substantial steps towards MM with large numbers of magnetic centres. Characteristic examples were the synthesis of a MM with 83 unpaired electrons and the synthesis of spherical antiferromagnets which pushed MM close to the border of magnetic nanoparticles which already found many applications in biomedicine.
In order to use MM as memory elements it was necessary to arrange them in arrays and find a way to address them individually. This problem was tackled by several teams in a coordinated mode. The most investigated system was Mn12, the cluster which started the gold race to molecular nanomagnetism. Layers and patterned structures of Mn12 were prepared and the structure and magnetic properties of the arrays were investigated using sophisticated instrumentation like synchrotron radiation, beta detected nuclear magnetic resonance (NMR), muon spin rotation etc.
Superconducting quantum interference device (SQUID) magnetometers of increasing sensitivity are a must in molecular nanomagnetism because of, among other factors, the low magnetic density of the materials. A revolutionary nano-SQUID was implemented using carbon nanotubes. It was expected that this device would render possible the measurement of the magnetisation of a single molecule. Hall probes were currently in the phase of commercialisation by the time of the project completion. Unique pieces of equipment were also a SQUID operating down to 10 mK and a pulsed electron paramagnetic resonance (EPR) equipment operating at 250 GHz.
Several possible routes to implement quantum computing using MM were suggested and exciting experiments were performed, showing quantum coherence in complex clusters which had an S= 0.50 ground state. The fascinating feature of the molecular approach was that of using very different shapes and types of magnetic centres to produce tailor made properties.
Exciting perspectives for applications emerged in the field of magnetic refrigeration. This was a long known technique, in which the application of a magnetic field on systems with high magnetic moment produced heat absorption. MM could be extremely efficient at low temperatures. The implementation of micron-sized and submicron-sized devices was also under way.
QUEMOLNA was also successful in terms of the development of the European research area (ERA), acting as catalyst for the initiation of a NoE, MAGMANet, where the RTN themes were developed. The use of magnetic molecules (MM) for quantum computing was developed in a SMALL project, approved by the Seventh Framework Programme.
The scientific output of QUEMOLNA was very high, both in terms of quantity and quality of scientific publications. The high degree of integration was demonstrated by over 200 papers which were jointly produced by two or more RTN units.
The stated goal of QUEMOLNA was that of investigating quantum effects in molecular nanomagnets, i.e. molecular systems which fell in the intermediate region between the one in which classic descriptions of magnetism worked and that in which quantum effects dominated. MM were investigated in order to understand quantum matter, opening exciting perspectives, e.g. for new types of magnetic memories using both classic and quantum approaches, such as quantum computing. In short, the goal was that of developing the so-called molecular spintronics. A key point to achieve success was the interdisciplinary team of groups which collaborated, with backgrounds as diverse as synthetic chemists, specialists in nanofabrication and solid state physicists with background in experimental techniques and theory.
The control of molecular design allowed for substantial steps towards MM with large numbers of magnetic centres. Characteristic examples were the synthesis of a MM with 83 unpaired electrons and the synthesis of spherical antiferromagnets which pushed MM close to the border of magnetic nanoparticles which already found many applications in biomedicine.
In order to use MM as memory elements it was necessary to arrange them in arrays and find a way to address them individually. This problem was tackled by several teams in a coordinated mode. The most investigated system was Mn12, the cluster which started the gold race to molecular nanomagnetism. Layers and patterned structures of Mn12 were prepared and the structure and magnetic properties of the arrays were investigated using sophisticated instrumentation like synchrotron radiation, beta detected nuclear magnetic resonance (NMR), muon spin rotation etc.
Superconducting quantum interference device (SQUID) magnetometers of increasing sensitivity are a must in molecular nanomagnetism because of, among other factors, the low magnetic density of the materials. A revolutionary nano-SQUID was implemented using carbon nanotubes. It was expected that this device would render possible the measurement of the magnetisation of a single molecule. Hall probes were currently in the phase of commercialisation by the time of the project completion. Unique pieces of equipment were also a SQUID operating down to 10 mK and a pulsed electron paramagnetic resonance (EPR) equipment operating at 250 GHz.
Several possible routes to implement quantum computing using MM were suggested and exciting experiments were performed, showing quantum coherence in complex clusters which had an S= 0.50 ground state. The fascinating feature of the molecular approach was that of using very different shapes and types of magnetic centres to produce tailor made properties.
Exciting perspectives for applications emerged in the field of magnetic refrigeration. This was a long known technique, in which the application of a magnetic field on systems with high magnetic moment produced heat absorption. MM could be extremely efficient at low temperatures. The implementation of micron-sized and submicron-sized devices was also under way.