Infrared photoresponse in twisted bilayer graphene

The capability to control the band structure by varying the twist angle in Moiré lattices provides an additional degree of freedom to explore light-matter interactions in these systems [1,2]. The occurrence of flat bands in magic-angle twisted bilayer graphene yield devices with transport features that are sensitive to temperature and irradiation. Under laser irradiation, these features will be clearly revealed from their bolometric and nonbolometric contributions to the photoresponse [3,4,5,6].  Here, we report on the photoresponse of magic-angle twisted bilayer graphene (MATBLG) Hall bar devices under a mid-infrared, continuous-wave irradiation. We measure the dependence of the photoresponse on gate voltage, while varying light intensity, polarization, and magnetic field, to unveil the complexity of the interplay between light and magnetic field in MATBLG. 

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