Related papers: Terahertz radiation due to random grating coupled …
As the variation of temperature alters the intrinsic carrier density in a semiconductor, numerical simulations indicate that the consequent variation of the relative permittivity in the terahertz regime provides a way to realize thermally…
We use intense terahertz pulses to excite the resonant mode (0.6 THz) of a micro-fabricated dipole antenna with a vacuum gap. The dipole antenna structure enhances the peak amplitude of the in-gap THz electric field by a factor of ~170.…
In the widely-studied two-color laser scheme for terahertz (THz) radiation from a gas, the frequency ratio of the two lasers is usually fixed at $\omega_2/\omega_1=$1:2. We investigate THz generation with uncommon frequency ratios. Our…
Spontaneous optical emission of graphene irradiated by intense single-cycle terahertz pulses was investigated experimentally and explained theoretically. We found that emitted photons are polarized predominantly perpendicular to the…
Graphene based THz modulators are promising due to the conical band structure and high carrier mobility of graphene. Here, we tune the Fermi level of graphene via electrical gating with the help of ionic liquid to control the THz…
We developed a hydrodynamic model of plasmonic crystals formed in the current-driven grating gate transistor structures. The model demonstrates that the quality factor of plasmonic resonances could be increased by using ungated regions with…
Terahertz (THz) emissions from fast electron and ion currents driven in relativistic, femtosecond laser-foil interactions are examined theoretically. We first consider the radiation from the energetic electrons exiting the backside of the…
We provide an analytical solution to the problem of scattering of electromagnetic radiation by a square-wave grating with a flat graphene sheet on top. We show that for deep groves there is a strong plasmonic response with light absorption…
Dipolaritons are mixed light-matter quasiparticles formed in double quantum wells embedded in microcavities. Due to resonant coupling between direct and indirect excitons via electronic tunnelling, dipolaritons possess large dipole moments.…
Frequency-selective or even frequency-tunable Terahertz (THz) photodevices are critical components for many technological applications that require nanoscale manipulation, control and confinement of light. Within this context, gate-tunable…
Spintronic emitters are a unique class of terahertz (THz) sources due to their quasi-two-dimensional geometry and thereby their capability to couple to resonator near fields. Global excitation of the emitters often obstructs the intricate…
We experimentally characterized terahertz (THz) radiation emitted from laser-wakefield acceleration (LWFA) driven at 100-TW laser power. Simultaneous measurements of the laser energy, electron-bunch charge, and THz energy reveal a quadratic…
We report on a detailed study of the terahertz (THz) photoresistivity in a strained HgTe three-dimensional topological insulator (3D TI) for all Fermi level positions: inside the conduction and valence bands, and in the bulk gap. In the…
We apply terahertz (THz) near-field streaking in a nanofocusing geometry to investigate plasmon polariton propagation on the shaft of a conical nanotip. By evaluating the delay between a streaking spectrogram for plasmon-induced…
Backward terahertz radiation can be produced by a high-intensity laser normally incident upon an underdense plasma. It is found that terahertz radiation is generated by electrons refluxing along the bubble shell. These shell electrons have…
A laser pulse composed of a fundamental and an appropriately phased second harmonic can drive a time-dependent current of photoionized electrons that generates broadband THz radiation. Over the propagation distances relevant to many…
The effect of the photoinduced absorption of terahertz (THz) radiation in a semi-insulating GaAs crystal is studied by the pulsed THz transmission spectroscopy. We found that a broad-band modulation of THz radiation may be induced by a…
Frequency-angular distributions for THz emission in the range of 0.1 - 3 THz generated in a single-color laser filament plasma situated both under and without electrostatic field are for the first time experimentally studied. The angular…
Graphene, owing to its ability to support plasmon polariton waves in the terahertz frequency range, enables the miniaturization of antennas to allow wireless communications among nanosystems. One of the main challenges in the demonstration…
The plane wave scattering and absorption by finite and infinite gratings of free-space standing infinitely long graphene strips are studied in the THz range. A novel numerical approach, based on graphene surface impedance, hyper-singular…