Berlin 2015 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 7: Graphene: THz, NIR and Transport Properties (HL with O/TT)
O 7.2: Vortrag
Montag, 16. März 2015, 09:45–10:00, ER 270
Mechanically Modulated Graphene for THz-Nanoelectronics. — •Jonas Sichau1, Timothy Lyon1, August Dorn1, Amaia Zurutuza2, Amaia Pesquera2, Alba Centeno2, and Robert Blick1 — 1Center for Hybrid Nanostructures, Institutes of Nanostructure and Solid State Physics, University of Hamburg, Jungiusstrasse 11c, 20355 Hamburg, Germany. — 2Graphenea S.A., 76 Tolosa Hiribidea, Donostia-San Sebastian, E-20018, Spain.
Graphene offers very high charge carrier mobility and a mean free path of several microns at room temperature. Consequently, it is a promising material for THz electronics [1]. For flat monolayer graphene, studies on microwave-photo excited transport have found spin resonance and zero-field pseudo-spin splitting [2]. The aim of our work is to investigate spatially modulated graphene under microwave excitation. Once carriers are propagating ballistically through the undulated graphene sheet, it is predicted that THz-radiation should be emitted [1].
We fabricated extremely large graphene membranes of up to 1 mm side lengths and transferred these onto a SiO2-substrate. The pitch and height of the mechanical modulation are of the order of 200 nm and 50 nm, respectively. The measurements are performed with a variable temperature insert (VTI) at magnetic fields up to 12T. The microwave signal is coupled to the sample via a micro inductor forming a resonator with the graphene sheet. With this configuration we are able to probe magnetotransport and the interaction with electromagnetic radiation.
[1] Tantiwanichapan et al., Nanotechnology 24, 375205 (2013)
[2] Mani, R.G. et al., Nat. Commun., 3:996 (2012)