Tuesday July 26 at 16:00 Hrs., In Room F-12 Department of Physics Faculty of Physical Sciences and Mathematics at the University of Chile Exam Grade student Camilo Osorio Ulloa be held to choose the degree of Master of Science majoring in physics.
The Review’s thesis entitled “Aspects of Antiferromagnetic Spintronics” which was directed by Professor Alvaro Nunez defend. They are all cordially invited. The summary of the thesis is attached
Spintronics is emerging as one of the most attractive and promising in condensed matter thanks to the diversity of phenomena present as the spin Hall effect, magneto-resistance giant currents. In spintronics studying antiferromagnets is interesting because within its properties are its natural abundance and the possibility of decreasing the temporal and spatial scales of phenomena present in them. An example is the use of these materials in magnetic memories, because thanks to the absence of net magnetization in the material antiferromagnetic may store information in smaller regions due to the null dipolar interaction between magnetic domains. This thesis is composed of three theoretical work aimed at developing the antiferromagnetic spintronics.
In the first part of the effective theory of a non-collinear antiferromagnetic system it is presented. For this we consider an anisotropic interaction and exchange between neighboring spines system. Through an order parameter belonging to the group of rotations we study the dynamics of low-energy excitations of the system resulting in a family of topological solitons which are described by the sine-Gordon equation. Finally we compare our results with numerical simulations of a system of magnetic moments getting completely concordant results.
The second part is the study of an antiferromagnetic magnónico glass. From a phenomenological theory study the dynamics of the magnetization field under the effect of exchange interaction and uniaxial anisotropy. Through a periodic modulation of the magnetic field anisotropy and characterize the spectrum of spin waves and band structure of the system.
In the third and final part of the study of the generation of spin currents it is presented by an antiferromagnetic network deformations due to quantum effects. This phenomenon, known as piezospintrónico effect is studied in two models of interest: antiferromagnetic graphene and zinc-blende antiferromagnetic. This effect, together with the Hall effect reverse spin can be useful for detecting currents pure spin.