Boolean Logic Devices comprised of Field-coupled Nanomagnets
Prof. Dr. Doris Schmitt-Landsiedel
Magnetic logic gates are nowadays an inherent part of the "ITRS Roadmap Emerging Research Devices": In the issue of 2007 it is clearly stated, that [... nanodevices, that implement both logic and memory in the same device would revolutionize circuit and nanoarchitecture implementation.] Ferromagnetic logic devices show exactly this property and turn out to be a paradigm shift in digital applications.
In a joint project with Lehrstuhl für Nanoelektronik at TUM (P. Lugli) and Notre Dame University (G. Csaba), microelectronic integration of field-coupled magnetic computing devices is investigated. The magnetic logic gates are engineered by ultrathin Co/Pt multilayers. An advantage of multilayer films is their sensitivity to ion irradiation. By using a focused Ga-ion beam we are able to change the magnetic properties i.e. reduce the perpendicular anisotropy to zero, write artificial domain walls and furthermore change the switching field very accurately by homogeneous ion irradiation. This is the precondition for magnetically field-coupled dots, devices and larger scale systems.
In the collaborative research we are focusing on the following questions:
- How to connect ferromagnetic gates to the electrical domain (electrical I/O)? This could already be demonstrated by input wires and output Hall sensors.
- How can magnetic gates be electrically clocked and synchronized? Several approaches are under investigation.
- What are the key requirements for magnetic logic gates embedded into large-scale integrated systems? For this objective, a high level simulation framework is under development.
This joint project is supported financially by DFG research grant: Field-coupled circuits in magnetic multilayers.
