相关论文: Quantum \v{C}erenkov Effect from Hot Carriers in G…
The generation of energetic electron bunches by the interaction of a short, ultra-intense ($I>10^{19} \textrm{W/cm}^2$) laser pulse with "grating" targets has been investigated in a regime of ultra-high pulse-to-prepulse contrast…
Graphene is promising for nanoscale, efficient, ultra-fast photo- and opto-electronic devices because of its remarkable electrical and optical properties, such as fast electron relaxation and heat dissipation. Here, we realize…
Graphene is considered to be plasmon active only up to the infrared based on combined tight binding model and random phase approximation calculations. Here we show that the optical properties of graphene as measured by ellipsometry and…
Electromagnetic fields bound tightly to charge carriers in a two-dimensional sheet, namely surface plasmons, are shielded by metallic plates that are a part of a device. It is shown that for epitaxial graphenes, the propagation velocity of…
Modulating the amplitude and phase of light is at the heart of many applications such as wavefront shaping, transformation optics, phased arrays, modulators and sensors. Performing this task with high efficiency and small footprint is a…
Electromagnetic processes associated with a charged particle moving in a strong circular magnetic field is considered in cylindrical coordinates. We investigate the relation between the vacuum curvature emission and Cherenkov emission and…
We perform a comprehensive analysis of the spectrum of graphene plasmons which arise when a pair of sheets are confined between conducting materials. The associated enhanced local fields may be employed in the manipulation of light on the…
Metamaterials have recently established a new paradigm for enhanced light absorption in state-of-the-art photodetectors. Here, we demonstrate broadband, highly efficient, polarization-insensitive, and gate-tunable photodetection at room…
Cherenkov radiation of charged particles moving with superluminal velocities in transparent media is a well-studied phenomenon with a plethora of applications. Its microscopic origins can be traced to the polarization of atomic shells,…
High energy particles traversing the Universe through the cosmic microwave backgroung radiation can, in principle, emit Cherenkov radiation. It is shown that the energy threshold for this radiation is extremely high and its intensity would…
Inelastic electron tunneling provides a low-energy pathway for the excitation of surface plasmons and light emission. We theoretically investigate tunnel junctions based on metals and graphene. We show that graphene is potentially a highly…
Graphene has shown great potentials for high-speed photodetection. Yet, the responsivities of graphene-based high-speed photodetectors are commonly limited by the weak effective absorption of atomically thin graphene. Here, we propose and…
Infrared plasmons in doped graphene nanostructures produce large optical absorption that can be used for narrow-band thermal light emission at tunable frequencies that strongly depend on the doping charge. By virtue of Kirchhoff's law,…
The unique optoelectronic properties of graphene [1] make it an ideal platform for a variety of photonic applications [2], including fast photodetectors [3], transparent electrodes [4], optical modulators [5], and ultra-fast lasers [6].…
We point out that plasmons in doped graphene simultaneously enable low-losses and significant wave localization for frequencies below that of the optical phonon branch $\hbar\omega_{Oph}\approx 0.2$ eV. Large plasmon losses occur in the…
The ultrafast dynamics of excited carriers in graphene is closely linked to the Dirac spectrum and plays a central role for many electronic and optoelectronic applications. Harvesting energy from excited electron-hole pairs, for instance,…
Electrons in graphene, behaving as massless relativistic Dirac particles, provide a new perspective on the relation between condensed matter and high-energy physics. We discuss atomic collapse, a novel state of superheavy atoms stripped of…
In recent years, we have seen a rapid progress in the field of graphene plasmonics, motivated by graphene's unique electrical and optical properties, tunabilty, long-lived collective excitation and their extreme light confinement. Here, we…
An alternative method of generation of Cerenkev radiation is proposed over here with the help of a rotating source and a reflector. The principle is that, if we focus a narrow beam of light on to source of light is rotated with certain…
Although electrons and photons are intrinsically different, importing useful concepts in optics to electronics performing similar functions has been actively pursued over the last two decades. In particular, collimation of an electron beam…