DAVID MELE

These findings demonstrate that electroluminescence can be observed for the first time in graphene, a material without a band gap, revealing infrared emission beyond its natural incandescence under certain conditions. This unexpected phenomenon is accompanied by an exceptionally efficient radiative energy transfer between graphene and its encapsulant, hexagonal boron nitride (hBN), which can account for up to 75% of the total dissipated electrical power.

Our work allows assessing the intrinsic frequency limits of GFETs using velocity saturation associated with Zener–Klein tunneling and opens perspectives “beyond-GFETs”, using plasma resonance techniques for sub-THz detection. The figure of merit is the fmax/fT ratio which increases from ≲0.2 in the mobility-limited regime, over ~1 in the velocity-saturation regime, up to ≳5 in the Zener–Klein regime. The latter offers promising perspectives in RADAR and GSM applications.

This demonstration of Dirac plasmon in graphene RF electronics paves the way to plasma resonance transistors for microwave detection in the sub-THz domain for wireless communication.

These results, obtained in a one-dimensional condensed matter system, confirm the non pertubative prediction of Schwinger (1951) concerning the instability of vacuum with respect to the creation of particle-antiparticle pairs under strong electric field and promotes graphene as a laboratory on-a-chip for quantum electrodynamics (QED).

This paper reports on a systematic study of the plasmonic properties of periodic arrays of gold cylindrical nanoparticles in contact
with a gold thin film. Such plasmonic substrates combining both advantages of the propagative and localised surface plasmons could
have large applications in enhanced spectroscopies.

In this paper we present high frequency field effect transistors based on graphene nanoribbons arrays (GNRFETs). The high frequency performances of our GNRFETs are already significant at low bias. At 300 mV drain source voltage, the highest intrinsic (extrinsic) cut-off frequency ft reaches 82 (18) GHz and the extrinsic maximum oscillation frequency fmax is 20 GHz, which is promising for low power applications.

This study refines the dielectric characterization of hexagonal boron nitride (hBN) in terms of low-field permittivity and high-field strength and conductivity up to the breakdown voltage using DC and RF transport in hBN capacitor series of variable thickness in the 10–100 nm range. We deduce an out-of-plane low field dielectric constant ε//=3.4±0.2 consistent with the theoretical prediction that narrows down the generally accepted window ε//=3–4. The DC-current leakage at high-field is also found to obey the Frenkel-Pool law for thermally-activated trap-assisted electron transport.

This work exploits the total internal reflection of Dirac Fermion across optics-inspired Klein tunnelling barriers in a graphene device and unveils the existence of transmission plateaus and their dependencies on the phonon scattering length.