WFU Department of Physics Wake Forest University

 

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WFU Physics Colloquium

TITLE: Pulsed Inverse Spin Hall Effect in Organic Semiconductors and Organic Trihalide Perovskites

SPEAKER: Professor Dali Sun,

Department of Physics
North Carolina State University

TIME: Wednesday January 25, 2017 at 4:00 PM

PLACE: Room 101 Olin Physical Laboratory


Refreshments will be served at 3:30 PM in the Olin Lounge. All interested persons are cordially invited to attend.

ABSTRACT

Organic semiconductors (OSECs) are promising materials for spintronics applications mainly because of the expected long spin relaxation time that originates from the light elements in their building blocks. Usually the OSEC are used in organic spintronics as interlayer between two ferromagnetic electrodes in organic spin-valve devices. In this case the spin-polarized carriers are generated in the OSEC by electrical ‘spin-injection’, and characterized by the giant magnetoresistance effect. Recently, however a second method for generating pure ‘spin-current’ has been introduced, namely ‘spin-pumping’ induced in the OSEC by resonant microwave absorption in a ferromagnetic substrate. This new method opens a new route for studying spin transport in OSECs, as well as spin-to-charge conversion obtained by the inverse spin-Hall effect, in spite of the inherent weak spin-orbit coupling in these materials. In this talk, I will describe a novel method of ‘pulsed spin-pumping’ that enables investigation of the inverse spin-Hall effect response in various OSECs ranging from pi-conjugated polymers with strong SOC that contain intrachain platinum atoms, to weak SOC polymers, to C60 films, where the SOC is predominantly caused by the molecule surface curvature. I will also present recent studies of organometal trihalide perovskites spintronics using both ‘spin-pumping’ and ‘spin-injection’.



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100 Olin Physical Laboratory
Wake Forest University
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