Over the past 150 years, many of the greatest questions in physics, spanning astronomical dimensions to quarks, have addressed how particles can emerge in continuous fields.
We will open a window into the behavior and control of some of the least explored and most puzzling objects in nanomagnetism: three-dimensional (3D) magnetic solitons (MSs).
These are spatially localized stable magnetization textures that have particle-like properties and are expected to move and interact in 3D in magnetic crystals and heterostructures in a similar manner to ordinary particles. Until now, their theoretical study has been restricted to simple models.
The experimental study of individual 3D MSs is nearly unexplored.
This is a result of their deep-sub-micron size and a current lack of suitable characterization techniques. We bring together four complementary research groups with expertise in theoretical descriptions of magnetism, device physics and magnetic characterization with high spatial and temporal resolution. Methodological breakthroughs by the partners will enable new fundamental theoretical and experimental insights into the nucleation, stability, dynamics and transport of 3D MSs, which are predicted to be influenced strongly by their nontrivial topology. Particular attention will be paid to the manner in which 3D MSs can be controlled and manipulated dynamically.
This project will open the field of 3D magnetization textures at the nanoscale to fundamental science.
3D MSs are foreseen to play the role of information carriers that can move freely in any spatial direction and to offer a key advance over conventional 2D magnetization textures. Results from the project will provide guidelines for their use in applications that include magnetic storage technology and neuromorphic information processing systems and enable the realization of pervasive new 3D device concepts.
- Establishment of a material-specific model for magnetic hopfions. Assessment of static, dy-
namic and transport properties of magnetic hopfions and their interaction with electrons.
- Computational search of hopfion-hosting magnetic materials using high-throughput ab initio
calculations. Development of a spin-lattice model.
- Simulation of electron optical phase images and electron energy-loss spectra of hopfions for
comparison with experimental results obtained using off-axis electron holography and EMCD.
- Experimental observation of hopfions in ferromagnets using off-axis electron holography.
- Experimental observations of hopfions in antiferromagnets using EMCD.
- Observation of chiral bobbers at room temperature.
- Observation of chiral bobbers and magnetic globules in geometrically-confined structures.
- In situ imaging of magnetic states in non-standard régimes.
- Nucleation and dynamics of hybrid magnetic solitons induced by spin-transfer torque.
- Light-induced manipulation of 3D magnetic solitons.
- Predictions of parameters, for which solitons such as MGs are stable and the identification of
material combinations to realize these parameters.
- Synthesis of materials and systems with appropriate interfacial coupling for the formation of
- Characterization of 3D magnetic solitons in multilayers using imaging and magnetotransport.
- Demonstrations of processes necessary for applications based on MGs.
- Development of instrumentation for imaging individual nanoscale magnetic textures in an ex-
ternal magnetic field that can be applied in any direction in the TEM.
- Development of instrumentation for the fully automated magnetic imaging of weak and 3D
nanoscale magnetization textures of individual magnetic solitons in the TEM.
- Atomic-resolution EMLD and EMCD of ferromagnetic and antiferromagnetic spin textures.
- Imaging of 3D magnetic textures with ns temporal resolutio