Chirality

Magneto-electric effects

The interaction of static electric (E) and magnetic fields (B) with matter provides valuable spectroscopic information and gives rise to a number of important effects. The linear or quadratic action of a static electric- or magnetic- field gives rise to well known phenomena. However, their combined action is a much rarer phenomenon. Bilinear birefringence phenomena have been reported by Roth and Rikken [1-2], but the combined action of an electric and a magnetic field on absorption has never been observed in a liquid. Such an effect may be termed magneto- electric dichroism. From considerations of symmetry, the phenomenon is expected to be circular differential in a chiral liquid in crossed electric and magnetic fields, E_B ; in achiral liquids it requires the inclusion of spatial dispersion and can also arise in parallel fields. We have set up an experiment that aims to observe these effects.

This work is in collaboration with Dr. Geert Rikken (Pulsed magnetic field lab, LNCMP, Toulouse).

[1] T. Roth and G.L.J.A. Rikken, Phys. Rev. Lett., 88 (2002) 063001.
[2] T. Roth and G.L.J.A. Rikken, Phys. Rev. Lett., 85 (2000) 4478.