Magnetoelectric devices for beyond CMOS applications

Among the technologies that could potentially represent a paradigm shift with respect to CMOS technology, spintronic computation presents several advantages to achieve area and power reduction. The possibility to perform multifrequency processing and the non-volatility of the magnetic materials could provide new functionalities to circuit designers for various applications. However, a major limitation for the realization of spintronic devices is the lack of a scalable and energy efficient transducer. A promising route for both low energy and an efficient control of the magnetization is the usage of the magnetoelectric effect, which couples electric fields to the magnetization. The magnetoelectric transducer consists of piezoelectric-magnetostrictive compounds (e.g. bilayers), in which the coupling between the electric and the spin domain occurs via strain. The strain induced in the piezoelectric layer by the applied electric field is transferred to the magnetostrictive film that in turn changes its magnetic state. The inverse mechanism, i.e., a voltage generation by the strain associated to a change in the magnetization orientation, also exist. The application in spintronic devices requires a detailed understanding of the coupling mechanism, the magnetization behavior as well as the development of material systems to enhance the coupling efficiency.

Within the thesis, the student will characterize magnetoelectric devices based on different piezoelectric/magnetic systems and will study the magnetoelectric coupling and the magnetization control in both static (DC) and radio-frequency regime. This will allow to assess the potential of magnetoelectric devices for advanced spintronic logic or memories applications. The experimental work will be supported by modeling activities (materials, devices, circuits) in the spintronics group at imec. The student should have a strong interest in electrical characterization of devices as well as in leading edge research topics on magnetism and magnetic materials.​