Electrons on a dielectric liquid-vapor interface. Stability in presence of normal magnetic field

The capillary wavelength instability of a charged liquid surface due to coupling between surface deformation and charge compression may be modified by altering the transport properties of the charges along the surface. For gas-like electrons, a normal magnetic field lessens the charge density softening of the capillary mode and renders the damped transverse mode unstable at exactly the same charge conditions at which the capillary mode goes unstable in zero field. For solid-like electrons exhibiting shear elasticity, on the other hand, the magnetic field has little effect on the softening of the surface deformation modes. Systems to which these considerations are applicable are electrons on and under a liquid helium surface, and ions at the demixtion interface of ³He-⁴He mixtures.