Spin-orbit and exchange proximity effects in 2d materials
DIPC Seminars
- Speaker
-
Jaroslav Fabian, University of Regensburg
- When
-
2017/06/23
14:00 - Place
- Donostia International Physics Center
- Add to calendar
- iCal
Graphene
and novel 2d materials offer new perspectives for spintronics [1]. However,
graphene has no band gap, so its spintronic applications will be limited to
being a highly efficient spin transfer channel. Heterostructures of graphene
and two-dimensional transition-metal dichalcogenides (TMDC) are emerging as
systems in which both orbital and spin properties can be controlled by gating,
thus offering a materials basis for spintronic applications, such as bipolar
spin devices. We have proposed that graphene on TMDCs can be used in
optospintronics [2], since the direct gap of TMDCs allows optical spin
orientation, with the successive transfer of spin into graphene. But these van
der Waals stacks also yield interesting fundamental physics. We have recently
shown that graphene on WSe2 exhibits an inverted band structure, which leads to
helical edge states in graphene nanoribbons on WSe2 [3], with a bulk
spin-orbit gap of about 1 meV, which is giant when compared to 24 micro eV in
pristine graphene. I will also mention our most recent results the proximity
effects in bilayer graphene as well as on engineering the proximity exchange in
graphene and TMDCs in tunnel junctions with ferromagnetic metals [4].
1.
W. Han, R. Kawakami, M. Gmitra, and J. Fabian, Nature Nanotechnology 9, 794
(2014)
2. M. Gmitra and J. Fabian, Phys. Rev. B 92, 155403 (2015)
3. M. Gmitra, D. Kochan, P. Högl, and J. Fabian, Phys.
Rev. B 93, 155104 (2016)
4. K. Zollner, M. Gmitra, T. Frank, and J. Fabian,
Phys. Rev. B 94, 155441 (2016)