Kolloquiumsvortrag: Hot spins and molecules: new ideas for a THz “green” information technology
Institut für Materialwissenschaft, Kaiser Str. 2, Geb.C , Raum "Aquarium"
Prof. Markus Münzenberg (Universität Greifswald)
Hot spins and molecules: new ideas for a THz “green” information technology
Spinelectronics is exploiting the spin degree of freedom for novel information technology or devices. In my talk I will present future directions. These new ideas pave the way for low energy consumption, nanometer-scale building blocks for spin-based computing, and bridging timescales towards a THz spintronics. I will focus on two recent aspects of our research on organic materials for spinelectronic Devices and ultrafast excitation, accompanied by a fundamental introduction into the topic.
(i) Molecules formed by the fusion of three benzene rings, belong to the class of open-shell systems and are Carbon based systems that carry a spin. A spin-filter device is formed at the interface to a ferromagnet with 20% magnetoresistance effect near room temperature, demonstrating the use of such molecules as templates to engineer organic spin-filter barriers and quantum registers storing a single spin.
(ii) New techniques for the detection of ultrafast spin-currents have to be developed to bring spin-based information technology to ultrafast time scales. The spin-current bunches launched from a ferromagnet can be converted to picosecond charge currents. They can be quantitatively determined via THz emission. The pulses can be shaped and manipulated in frequency.
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