Seminar: Ultrafast spin dynamics across metal/semiconductor interfaces

The integration of the magnetic degree of freedom in current silicon technology is a captivating field of research which has raised renewed interest in the past few years. The increased ability to efficiently tailor the properties of hybrid metal-semiconductor devices has been one driving force. Moreover, such systems still allow to gain intriguing insights from the complex interplay of different mechanisms, both from the fundamental and applied physics point of view. If successful, this path can pave the way to the Spintronic (SPIN Transport electRONICS) paradigm, which is expected to improve the current Semiconductor paradigm in several respects through faster and energy-efficient devices, among others. These achievements are made possible thanks to the unique properties of magnetism in solid systems, as for instance the spin coherence time, seemingly longer than charge confinement times, and the spin interaction energy, smaller than pure electronic interactions. A viable Spintronic technology, however, requires the effective generation, transport, manipulation and detection of spins in solid-states devices. In this talk, I will propose a path towards the generation and transport of spin currents in silicon in the field of ultrafast demagnetization and the subsequent generation of superdiffusive currents in a thin magnetic film. The system under study - a nickel thin film grown on a passivated silicon semiconductor - offers a benchmark for the investigation of the interaction between optical, magnetic and electric properties in a simple device.