Magnonics with chiral magnets

Magnonics with chiral magnets

Introduction.

The chiral solitons stabilized by the DMI are very interesting because they can present advantages over skyrmions, since their movement is not gyro-tropic and they will be easier to control. Moreover, it is interesting to elucidate the advantages that they can present with respect to the domain walls. On the other hand, the theoretical techniques used to study the dynamics of magnetic structures are of two types: i) the introduction of a few collective variables to describe the structure and ii) the numerical resolution of the LLG equation. In the first case, a generalization of the method of collective variables recently developed is used, and it will be necessary to deduce the equations that govern the dynamics of collective variables. For linear structures such as domain walls and chiral solitons in two dimensions (thin films) the center of the structure forms a line and its dynamics can be described by an elastic line model. The rest of the collective variables (for example, the width) could qualitatively change the dynamics of the elastic line.

Objectives

Main objective is the study of the response of solitons in monoaxial chiral magnets to applied magnetic fields and spin transfer torques induced by polarized electric currents, by means of effective models of collective variables and numerical simulations of the Landau-Lifshitz-Gilbert equation (LLG)

Task to be developped

Mainly numerical techniques will be used, although it will also be necessary to apply analytical techniques. In particular, numerical resolution techniques of initial value problems will be used in deterministic and stochastic differential equations (explicit or implicit methods) and border value problems (relaxation methods). The analytical techniques will be of a perturbative nature and will be applied to cases where external forces are weak.

More Information please contact Victor Laliena or Javier Campo