The Netherlands Organization for Scientific Research has a couple of interesting things in the works, the first being next generation media storage. Dutch researcher Alexander le Fèbre has demonstrated that a field-emission current signal can be used to arrange the position of thousands of nanometre-sharp needles. These probes can be applied to write and read in new storage media with an extremely high density, using bits on a nanometre scale.

The development of the hard disk is reaching its technical limits because the entire disk is served by just a single head so the capacity of the disk and the reading and writing speed cannot expand much more in the future. Research into a memory based on probes from the University of Twente’s MESA+ research institute means able to control the position of each separate probe - essential for realizing a system with extremely high densities.

Le Fèbre's measurements show that a field-emission current signal can be used to adjust the position of the probes without these making direct contact with the storage medium. If a constant current is maintained and the applied voltage is varied, the distance between the probe apex and the storage medium can be adjusted from several nanometres to about 100 nanometres.

The resolution is sufficient for a probe-based storage system. However for practical applications, the current stability and the lifetime of the probes will need to be improved further so that the accuracy and reproducibility of positioning can be increased.

Dutch mathematician Anne Fey has been examining self-organization using probability calculations in mathematical sandpile models.

Practical applications are, for example, movements in the Earth's crust, stock market fluctuations and the formation of traffic jams.

These mathematical models are defined on a grid. Each grid point has a height, or quantity of sand, that must be below a limiting value. With each time interval, the height of one of the points increases. If a height exceeds a limiting value the sand must be moved to nearby points until all points are once again under the limiting value.

Although the rules of the model are simple, the wide-ranging behaviour that emerges from these is fascinating. Sandpile models exhibit various forms of self-organisation and patterns are formed which are stable over the course of time. That is seen most clearly in the case where only the height of the mid-point increases. The sand then spreads out symmetrically in highly angulated forms, in which fractal patterns develop. Fractal patterns have an infinite quantity of details in which designs are repeated on an increasingly smaller scale – this is comparable to ice crystals and certain corals.

In the other situations, the choice of the point where the height increases is random. Then 'self-organised criticality' occurs, a deeper form of self-organisation that is also studied in diverse research areas such as movements in the Earth's crust, stock market fluctuations and the formation of traffic jams.