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Ultrafast electrically driven nanoscale light sources are critical components in nanophotonics. Compound semiconductor-based light sources for the nanophotonic platforms have been extensively investigated over the past decades. However, monolithic ultrafast light sources with a small footprint remain a challenge. Here, we demonstrate electrically driven ultrafast graphene light emitters that achieve light pulse generation with up to 10 GHz bandwidth, across a broad spectral range from the visible to the near-infrared. The fast response results from ultrafast charge carrier dynamics in graphene, and weak electron-acoustic phonon-mediated coupling between the electronic and lattice degrees of freedom. We also find that encapsulating graphene with hexagonal boron nitride (hBN) layers strongly modifies the emission spectrum by changing the local optical density of states, thus providing up to 460 % enhancement compared to the grey-body thermal radiation for a broad peak centered at 720 nm. Furthermore, the hBN encapsulation layers permit stable and bright visible thermal radiation with electronic temperatures up to 2,000 K under ambient conditions, as well as efficient ultrafast electronic cooling via near-field coupling to hybrid polaritonic modes. These high-speed graphene light emitters provide a promising path for on-chip light sources for optical communications and other optoelectronic applications.
We propose a terahertz radiation source based on the excitation of plasma resonances in graphene structures by means of mixing two NIR laser signals with a THz difference frequency. The process is the photo-thermo-electric effect which has recently b
Interband optical transitions in graphene are subject to pseudospin selection rules. Impulsive excitation with linearly polarized light generates an anisotropic photocarrier occupation in momentum space that evolves at timescales shorter than 100fs.
In the model of gapped graphene, we have shown how the recently predicted topological resonances are solely related to the presence of an energy band gap at the $K$ and $K^prime$ points of the Brillouin zone. In the field of a strong single-oscillati
We study theoretically the interaction of ultrashort optical pulses with gapped graphene. Such strong pulse results in finite conduction band population and corresponding electric current both during and after the pulse. Since gapped graphene has bro
We study theoretically interaction of a bilayer graphene with a circularly polarized ultrafast optical pulse of a single oscillation at an oblique incidence. The normal component of the pulse breaks the inversion symmetry of the system and opens up a