Abstract
Temporal director fluctuations in nematic ordering were studied by computer simulation on the Lebwohl-Lasher model as well as by neutron-scattering experiments on the nematogen d-PAA. The time-series data have been analyzed by the rescaled-range method and in terms of the power spectrum in order to determine the Hurst exponent H. Theory and experiment are in good agreement. A value of H1 was found for the nematic phase, characterizing fractional Brownian motion, whereas H0.5, reflecting ordinary Brownian motion, applies in the isotropic phase. Field-induced crossover from fractional to ordinary Brownian motion was observed in the nematic phase.
| Original language | English |
|---|---|
| Journal | Physical Review Letters |
| Volume | 70 |
| Issue number | 12 |
| Pages (from-to) | 1834-1837 |
| Number of pages | 4 |
| ISSN | 0031-9007 |
| DOIs | |
| Publication status | Published - 1993 |
| Externally published | Yes |