Spin transport in graphene (Hee-Jun Yang, Sungkyunkwan Univ.)

Hee-Jun Yang
2014-04-11 pm 04:00 / EB1, E207
Spin transport in graphene
Heejun Yang
Assistant Professor, Department of Energy Science,
Sungkyunkwan University
Electronic devices based on spin transport are expected to play a major role in future information and communication technologies. In this respect, various aspects of spintronics were recently included in the ITRS (International Technology Roadmap for Semiconductors) road map.
Spin information processing will require the ability to inject, manipulate and detect spins [1]. For those functions, channel material is a key issue in the technology. While GaAs and Si have been the main stream candidates, they have encountered fundamental constraints governing the physics of spin transport.
In this seminar, I will present a set of experiments and ideas on an alternative route where the channel is no longer a conventional semiconductor but graphene. Graphene is expected to be a good candidate for spin transport thanks to its high mobility and its low spin-orbit coupling. In detail, three different concepts of spin transport in graphene will be presented; lateral spin valve where a spin diffusion length of 100 µm is demonstrated [2], spin transport in graphene without ferromagnet [3] and graphene-passivated ferromagnetic electrodes [4].
[1] Appl. Phys. Lett. 56, 665 (1990), S. Datta and B. Das ‘Electronics analog of the electro-optic modulator’
[2] Nature Physics 8, 557 (2012), B. Dlubak et al. ‘Highly efficient spin transport in epitaxial graphene on SiC’
[3] Heejun Yang et al. in preparation
[4] ACS Nano 6, 10930 (2012), B. Dlubak et al. ‘Graphene-Passivated Nickel as an Oxidation-Resistant Electrode for Spintronics’