1. Level (Type) of work:
Qualifying graduate thesis/Master thesis; PhD thesis.
2. Topic:
1) Determination of neutron lifetime in resonator structure.
2) Investigation of characteristics of magnetic nanostructure in a variable magnetic field.
3) Investigation of Т-odd effects at neutron passage through magnetic noncoplanar structures of various types.
4) Development of neutron reflectometry techniques for studying nanostructures under pressure.
5) Development of small-angle research techniques in a sliding geometry.
6) Studies of the structure of hydrogen film adsorbent.
3. Work objective:
1) Investigation of the relationship between the uncertainty and the parameters of nanostructure of resonator type. Study of conditions of achievement of maximum strengthening of neutron density.
2) Investigation of the dependence of time characteristics on the thickness of magnetic layers in a bilayer.
3) Comparative study of noncollinear and noncomplanar magnetic structures. Determination of left-right asymmetry by passing nonpolarized neutrons, elucidation of its relation to the structure parameters.
4) Elucidation of the mechanism of changes of the proximity phenomena depending on the compression-stretching of the bilayer.
5) Achievement of a nano-range in the measurement of the correlation length of inhomogeneous state of near-surface layer of a substance.
6) Creation of effective hydrogen storage.
4. Short description:
1) The elucidation of conditions of achieving high sensitivity in the measurement of magnetic characteristics of weak-magnetic layers will make it possible to study the structure of interfaces in magnetic/nonmagnetic bilayers. However, maximum amplification of a signal is limited by the uncertainty relation. In this connection, the establishment of a link between the uncertainty relation and nanostructure parameters becomes crucial.
2) Operation speed of nanoelectronic elements is determined by the volume of a nanostructure, however there is no linear dependence among them. The establishment of a real relationship between the characteristics in a magnetic field and the thickness of interacting layers is also a tool for determining the magnitude of interaction.
3) In view of the difference in transmission of a nonpolarized ensemble through a noncoplanar magnetic membrane, a number of important applications for practical purposes can be expected, as for instance, a separator of magnetic atoms.
4) The proximity effects are of principal importance in the physics of nanostructures, because they involve transfer of one order parameter to a medium with another order parameter. As a result, radically new phenomena are synthesized, which open the way to new engineering and technological applications. The application of pressure transforms the “proximate” into “more proximate”, and hence nonlinear behavior and still more interesting effects should be expected.
5) The advance into nanometer-scale region of determining the correlation length of near-surface inhomogeneous state will make it possible to progress in the research area of nanostructured phenomena in the plane, which is of importance for studying various manifestations of interactions at interfaces (e.g., coexistence of magnetism and superconductivity).
6) Basic requirements to hydrogen adsorbents: hydrogen mass in respect to carrier volume is 0.036 kg/l, used materials should be inert to oxygen and carbon monoxide, temperature adsorption-desorption interval should be within 20-200°С, hydrogen filling time is no more than 10 min. The studies that have been already carried out suggest that porous nanocrystalline materials on the basis of vanadium and titan nitrides meet these requirements.
5. Basic facilities and software:
Neutron reflectometer, small-angle spectrometer, diffractometer and spectrometer of inelastic scattering.
6. Results:
Preparation of publications and reports to conferences.
Defense of Diploma and PhD theses.
7. Minimum required time: 1-3 years
8. Supervisors:
Yurii Vasiljevich Nikitenko
9. Contact phone number and e-mail:
8-9636031256, 65-155, This email address is being protected from spambots. You need JavaScript enabled to view it.