Related papers: Effective Path Towards Relativistic Transients at …
The brightness of a light source defines its applicability to nonlinear phenomena in science. Bright low frequency terahertz (< 5THz) radiation confined to a diffraction-limited spot size is a present hurdle due to the broad bandwidth and…
A thin-disk regenerative amplifier with 3 kHz repetition rate pumps a second-order nonlinear mixing scheme providing femtosecond transients of maximum electric field strength beyond 330 MV/cm at a center frequency of 45 THz. This value…
To achieve high efficiency and good performance of spintronic terahertz sources, we propose and corroborate a remnant magnetization method to radiate continuously and stably terahertz pulses from W/CoFeB/Pt magnetic nanofilms without…
The availability of intense, ultrashort coherent radiation sources in the infrared region of the spectrum is enabling the generation of attosecond X-ray pulses via high harmonic generation, pump-probe experiments in the "molecular…
A novel method is presented for generating radiation using the beat wave associated with a bi-frequency laser pulse, to excite plasma oscillations in a plasma slab with a density gradient. By resonantly exciting a plasma wave, it can be…
We propose a method to generate isolated relativistic terahertz (THz) pulses using a high-power laser irradiating a mirco-plasma-waveguide (MPW). When the laser pulse enters the MPW, high-charge electron bunches are produced and accelerated…
Multi-longitudinal-mode lasers have been believed to be good candidates as pump sources for optical frequency conversion. However, we present a semi-classical model for frequency conversion of optical signals with a multimode pump laser,…
We demonstrate a low-noise frequency down-conversion of photons at 637 nm to the telecommunication band at 1587 nm by the difference frequency generation in a periodically-poled lithium niobate. An internal conversion efficiency of the…
High-power, continuously tunable narrowband terahertz (THz) sources are essential for advancing nonlinear optics, THz-driven material dynamics, and ultrafast spectroscopy. Conventional techniques typically impose a trade-off between pulse…
A model for THz generation by optical rectification using tilted-pulse-fronts is developed. It simultaneously accounts for (i) the spatio-temporal distortions of the optical pump pulse, (ii) the nonlinear coupled interaction of THz and…
Free-space strong-field terahertz (THz) pulses, generated via optical rectification of femtosecond lasers in nonlinear crystals, are pivotal in various applications. However, conventional Ti:sapphire lasers struggle to produce…
We demonstrate a table-top high-field terahertz (THz) source based on optical rectification of a collimated near-infrared pulse in gallium phosphide (GaP) to produce peak fields exceeding 300 kV/cm with a spectrum centered at 2.6 THz. The…
Mode-locked lasers (MLLs) have enabled ultrafast sciences and technologies by generating ultrashort pulses with peak powers substantially exceeding their average powers. Recently, tremendous efforts have been focused on realizing integrated…
Numerical investigations of multicycle terahertz pulse generation based on wafer stack and tilted pulse front pumped lithium niobate setups concerning the conversion efficiency and the resulting temporal shape and spectrum were performed.…
Relativistically moving dielectric perturbations can be used to manipulate light in new and exciting ways beyond the capabilities of traditional nonlinear optics. Adiabatic interaction with the moving front modulates the wave simultaneously…
We report bilayer-graphene field effect transistors operating as THz broadband photodetectors based on plasma-waves excitation. By employing wide-gate geometries or buried gate configurations, we achieve a responsivity $\sim 1.2V/W (1.3…
Coupling phase-stable single-cycle terahertz (THz) pulses to scanning tunneling microscope (STM) junctions enables spatio-temporal imaging with femtosecond temporal and \r{A}ngstrom spatial resolution. The time resolution achieved in such…
Optical pump-probe techniques like absorption spectroscopy and microwave conductivity are widely used to characterize the carrier dynamics in perovskites for optoelectronic applications. In contrast to the prevalent assumption of…
Nonlinear metasurfaces offer compact control over frequency conversion and wavefront shaping. However, existing approaches, often based on geometric phase, lack wavelength selectivity, resulting in static nonlinear responses. Here, we…
Nonlinear frequency conversion provides an elegant method to detect photons in a spectral range which differs from the pump wavelength, making it highly attractive for photons with inherently low energy. Aside from the intensity of the…