Related papers: Universal charts for optical difference frequency …
We present a general analysis of the influence of nonlinear optical absorption on terahertz generation via optical difference frequency generation, when reaching for the quantum conversion efficiency limit. By casting the equations…
We present a detailed analysis and comparison of dielectric waveguides made of CdTe, GaP, GaAs and InP for modal phase matched optical difference frequency generation (DFG) in the terahertz domain. From the form of the DFG equations, we…
Using optical technology for current injection and electromagnetic emission simplifies the comparison between materials. Here, we inject current into monolayer graphene and bulk gallium arsenide (GaAs) using two-color quantum interference…
Scattering-assisted synthesis of broadband optical pulses is recognized to have a cross-disciplinary funda-mental and application importance. Achieving full-waveform synthesis generally requires means for assessing the instantaneous…
In a semiconductor illuminated by a strong terahertz field, optically excited electron-hole pairs can recombine to emit light in a broad frequency comb evenly spaced by twice the terahertz frequency. Such high-order terahertz sideband…
Highly efficient terahertz (THz) wave sources based on difference frequency generation (DFG) process in nonlinear optical crystals play an important role for the applications of THz wave. In order to find more novel nonlinear crystals, here…
The terahertz spectral regime, ranging from about 0.1 to 15 THz, is one of the least explored yet most technologically transformative spectral regions. One current challenge is to develop efficient and compact terahertz emitters/detectors…
Terahertz Time-Domain Spectroscopy is a powerful technique for extracting the low-frequency optical properties of materials. However, the optical constants are difficult to determine directly from the experimental transfer function, such…
Graphene as a zero-bandgap two-dimensional semiconductor with a linear electron band dispersion near the Dirac points has the potential to exhibit very interesting nonlinear optical properties. In particular, third harmonic generation of…
A 2-D spatio-temporal analysis of terahertz generation by optical rectification of tilted-pulse-fronts is presented. Closed form expressions of terahertz transients and spectra in two spatial dimensions are furnished in the undepleted…
We analytically show how a superposition of beamlets produces terahertz radiation with greater spatial homogeneity and efficiency compared to tilted-pulse-fronts generated by diffraction gratings. The advantages are particularly notable for…
Graphene is conceivably the most nonlinear optoelectronic material. Its nonlinear optical coefficients in the terahertz (THz) frequency range surpass those of other materials by many orders of magnitude. This, in particular, allows one to…
The electromagnetic spectrum in the terahertz frequency region is of significant importance for understanding the formation and evolution of galaxies and stars throughout the history of the universe and the process of planet formation.…
Unpaired image dehazing has attracted increasing attention due to its flexible data requirements during model training. Dominant methods based on contrastive learning not only introduce haze-unrelated content information, but also ignore…
The nonlinear metamaterials have been shown to provide nonlinear properties with high nonlinear conversion efficiency and in a myriad of light manipulation. Here we study terahertz generation from nonlinear metasurface consisting of single…
The intense terahertz (THz) pulses facilitate the observation of various nonlinear optical effects and manipulation of material properties. In this work, we report a convenient approach that can produce strong broadband terahertz pulses…
Graphene has unique properties paving the way for groundbreaking future applications. Its large optical nonlinearity and ease of integration in devices notably makes it an ideal candidate to become a key component for all-optical switching…
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…
Perfect absorption of radiation in a graphene sheet may play a pivotal role in the realization of technologically relevant optoelectronic devices. In particular, perfect absorption of radiation in the terahertz (THz) spectral range would…
The majority of sources of coherent optical radiation rely on laser oscillators driven by population inversion. Despite their technological importance in communications, medicine, industry, and other fields, it remains a challenge to access…