FOM PhD Simone Belli wins Italian physics prize
Simone Belli MSc from the Institute for Theoretical Physics (ITF) at Utrecht University has won the Fontana Prize 2012 from the Società Italiana di Fisica. He has received this prize for his contribution to the thermodynamics of liquid crystals. The Fontana Prize, worth €1000, is awarded each year to a young Italian researcher. This year the prize was specifically awarded to a researcher active in the field of soft condensed materials. The prize will be awarded in mid-September during the annual congress of the Società Italiana di Fisica in Naples.
Liquid crystals, which are frequently used in displays, often consist of identically oriented cigar-shaped or pancake-shaped particles. Belli, however, is doing theoretical research into the spontaneous alignment of brick-shaped nanoparticles. On the one hand, theories predict that at high concentrations such nanobricks will spontaneously align themselves in two directions so that a liquid crystal arises with two optical axes instead of the usual single axis. On the other hand, both theory and experiments reveal that this 'biaxial state' is extremely difficult to stabilise due to crystallisation or separation.
Belli's calculations have revealed that impure mixtures of nanobricks with a wide range of dimensions have a surprisingly large tendency to align themselves biaxially. Crystallisation and separation take place far less often in such mixtures. This not only explains the surprising and uncomprehended stability of biaxial arrangements of nanobricks in the experiments of former FOM PhD Esther van der Pol, but also suggests in which direction building blocks can be sought for biaxial molecular liquid crystals with display applications. Or as Belli's supervisor Dr. René van Roij says: "The best alignment usually occurs in the purest materials, but in this case Belli has shown that impurity is fundamentally important for the stability of biaxial liquid crystals".
Belli published his work together with Marjolein Dijkstra (Debye Institute for Nanomaterials Science) and René van Roij (ITF) last year in Physical Review Letters: Polydispersity Stabilizes Biaxial Nematic Liquid Crystals, Physical Review Letters 107, 148303 (2011).
Contact
Simone Belli +31 (0)30 253 5905
René van Roij +31 (0)30 253 7579