Fig. 2: GF operation in MIR detection mode.
From: Bidirectional mid-infrared communications between two identical macroscopic graphene fibres
a Schematic of 1 mm long GF suspended between gold electrodes illuminated by 4 μm wavelength femtosecond laser (fluence = 4.9 W cm−2) at constant voltage bias of 3 mV. b Photoresponse of GF when the laser spot moved from one electrode to the other. The position of the laser spot along the GF length is labeled next to the response signal. Photoresponse curves are shifted for clarity. c A comparison of responsivities of state-of-the-art MIR photodetectors with GF. Raman spectra, the corresponding MIR response, and the simplified schematics of presumed photo-carrier transport mechanisms of GF (d–f), highly oriented pyrolytic graphite (HOPG, g–i) and reduced graphene oxide fiber (RGOF, j–l), respectively. The solid circles in e, h, and k represent electrons, and the hollow circles represent the hole. The orange lines in k represent sp3-hybridized topologic defects.
