相关论文: Giant and Broadband THz and IR Emission in Drift-b…
Cherenkov radiation in artificial structures experiencing strong radiation enhancements promises important applications in free-electron quantum emitters, broadband light sources, miniaturized particle detectors, etc. However, the momentum…
As charged particles surpass the speed of light in an optical medium they produce radiation - analogously to the way jet planes surpass the speed of sound and produce a sonic boom. This radiation emission, known as the Cherenkov effect, is…
Based on a structure consisting of a single graphene layer situated on a periodic dielectric grating, we show theoretically that intense terahertz (THz) radiations can be generated by an electron bunch moving atop the graphene layer. The…
Cherenkov radiation enables high-energy particle identification through its velocity-dependent emission angle, yet conventional detectors fail to detect momenta beyond tens of GeV/c owing to the absence of natural materials with near-unity…
Controlling directional emission of nanophotonic radiation sources is fundamental to tailor radiation-matter interaction and to conceive highly efficient nanophotonic devices for on-chip wireless communication and information processing.…
In the framework of full Maxwell equations, we systematically study the electromagnetic radiation, namely the transition radiation, when a swift electron perpendicularly crosses a monolayer graphene. Based on the plane wave expansion and…
We describe very fast electron dynamics for a graphene nanoribbon driven by a control electromagnetic field in the terahertz regime. The mobility as a function of bias possesses a large threshold value when entering a nonlinear transport…
Cherenkov radiation is generally believed to be threshold-free in hyperbolic metamaterials owing to the extremely large photonic density of states in classical local framework. While recent advances in nonlocal and quantum effects extend…
Carbon nanomaterials such as carbon nanotubes and graphene have proved to be efficient building blocks for active optoelectronic devices. Especially, the exotic properties of crystalline graphene, such as a linear/gapless energy dispersion,…
We theoretically study the transition radiation of bulk and surface electromagnetic waves by an electron crossing an interface between a layered superconductor and an isotropic dielectric. We assume that the direction of the electron motion…
The efficient amplification and lasing of electromagnetic radiation at terahertz (THz) frequencies is a non-trivial task achieved mainly by quantum cascade laser configurations with limited tunability and narrowband functionality. There is…
Cherenkov radiation provides a valuable way to identify high energy particles in a wide momentum range, through the relation between the particle velocity and the Cherenkov angle. However, since the Cherenkov angle depends only on…
We study broadband terahertz (THz) conductivity and ultrafast photoconductivity spectra in lithographically fabricated multilayer epitaxial graphene nanoribbons grown on C- face of 6H-SiC substrate. THz near-field spectroscopy reveals local…
Control over the spontaneous emission of light through tailored optical environments remains a fundamental paradigm in nanophotonics. The use of highly-confined plasmons in materials such as graphene provides a promising platform to enhance…
The active control of matter by strong electromagnetic fields is of growing importance, with applications all across the optical spectrum from the extreme-ultraviolet to the far-infrared. In recent years, phase-stable terahertz (THz) fields…
According to quantum electrodynamics, in a strong magnetic field that is constant and spatially uniform, the vacuum becomes polarized with a refractive index greater than unity. As a result, ultra-relativistic charged particles travelling…
When high-frequency radiation is incident upon graphene subjected to a perpendicular magnetic field, graphene absorbs incident photons by allowing transitions between nearest LLs that follow strict selection rules dictated by angular…
A novel broadband technique to effectively launch plasmons along a single graphene layer at terahertz (THz) frequencies is proposed. To this end, the coupling of the electromagnetic wave from a readily available plasmonic waveguide…
A recent study [PRB 100, 075427 (2019)], finally, demonstrated plasmon-analog of refractive index enhancement in metal nanostructures, which has already been studied in atomic clouds for several decades. Here, we simply utilize this…
A scheme for generation of monochromatic Cherenkov radiation in a thin dielectric layer is proposed. The electrons travel in vacuum parallel to a dielectric, exciting a single synchronous electromagnetic waveguide mode. The proposed scheme…