https://doi.org/10.1007/s100510050669
Magnetic field induced instabilities of a doped lyotropic hexagonal phase
1
Laboratoire de Physique de la Matière Condensée (CNRS, URA 792) ,
Collège de France, 11 place Marcelin Berthelot, 75231 Paris Cedex 05, France
2
UMR CNRS-Elf Atochem, 95 rue Danton, 92303 Levallois-Perret Cedex, France
3
Laboratoire de Physique des Solides, Bâtiment 510, Université Paris-Sud Orsay,
91405 Orsay Cedex, France
Received:
10
February
1998
Published online: 15 March 1999
A new anisotropic magnetic fluid is obtained using a colloidal suspension of magnetic particles of nanometric size (ferrofluid) as a component of a swollen lyotropic hexagonal phase. This doped hexagonal system exhibits specific behaviors when submitted to a magnetic field of weak intensity. The field-induced instabilities are described and interpreted; they result from a high anisotropy of the magnetic susceptibility of the medium, which is measured. It is finally shown that the magnetic properties of the doped hexagonal phase allows one a determination of the compression modulus of the system.
PACS: 75.50.Mm – Magnetic liquids / 82.70.Dd – Colloids / 61.30.Gd – Orientational order of liquid crystals; electric and magnetic field effects on order
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1999
