Konstantinov A. Thermopolarization effects in superfluid Bose systems

The thesis is devoted to the theoretical study of polarization processes and thermopolarization mechanisms of superfluid Bose systems. It is predicted that oscillations of temperature during the propagation of the third sound in a thin superfluid film cause the appearance of an alternating electric field in the surrounding space (non-stationary thermoelectric effect). The magnitude of this field depends significantly on the substrate type and the method of its coating. It is shown that the influence of thermally activated vortices on this effect is weak even near the superfluid transition. It is also predicted that a heat flux induced by the temperature gradient in superfluid helium that is placed in a magnetic field generates an electric field. The magnitude of the field significantly depends on the shape of the helium-containing sample and on the direction of the magnetic field with respect to the sample. The existence of this effect as a result of both static and time-dependent temperature gradients is established. The thesis also develops the microscopic theory of polarization of the superfluid system in the model of a weakly non-ideal Bose gas. In the context of this model, it is established that a vortex in a superfluid film creates an electric potential above the film. This potential has the form of a dipole’s potential, allowing one to assign a dipole moment to the vortex.