相关论文: Terahertz generation by optical rectification in u…
Measuring terahertz waveforms in terahertz spectroscopy often relies on electrooptic sampling employing a ZnTe crystal. Although the nonlinearities in such zincblende semiconductors induced by intense terahertz pulses have been studied at…
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=$1:2. We investigate THz generation with uncommon frequency ratios. Our…
A laser pulse composed of a fundamental and an appropriately phased second harmonic can drive a time-dependent current of photoionized electrons that generates broadband THz radiation. Over the propagation distances relevant to many…
Scaling femtosecond terahertz (THz) and ultraviolet (UV) sources to high repetition rates is essential for high-throughput ultrafast spectroscopy and imaging applications. Yet, their efficient generation at high average power remains…
A highly efficient, practical approach to high-energy terahertz (THz) generation based on spectrally cascaded optical parametric amplification (THz-COPA) is introduced. The THz wave initially generated by difference frequency generation…
Polarization analyses of the terahertz (THz) emission from Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ whisker crystals used for superconducting THz emitters were conducted. The THz emission mode was estimated by a simple polarization…
Highly-efficient optical generation of narrowband terahertz (THz) radiation enables unexplored technologies and sciences from compact electron acceleration to charge manipulation in solids. State-of-the-art conversion efficiencies are…
The polarization direction of an electromagnetic field changes and eventually reaches a steady state when propagating through a birefringent material with off axis absorption or gain. The steady state orientation direction depends on the…
We have observed short-lived optical birefringence in a CH$_3$NH$_3$PbBr$_3$ single crystal induced by a powerful nearly single-cycle terahertz pulse. Apart from the instantaneous contribution that follows the profile of the squared pump…
We study the Terahertz (THz) emission mechanism in BSCCO with an external magnetic field theoretically. The total power is proportional to the square of the number of layers and the frequency. Under the small size limitation, the angular…
We present a method to measure quadratic Terahertz optical nonlinearities in Terahertz time-domain spectroscopy. We use a rotating linear polarizer (a polarizing chopper) to modulate the amplitude of the incident THz pulse train. We use a…
This study investigates different type of semiconductor crystals including assessing several physical characteristics and relevant parameters, which are refraction index, multiphoton absorption coefficient, electro-optic coefficient,…
Organic crystals offer promising potential for THz generation, but face limitations in wavelength tunability and damage threshold. By applying tilted pulse front pumping to organic crystals an additional degree of freedom is introduced into…
We demonstrate an efficient procedure for terahertz-wave radiation generation by applying a nonlinear wavelength conversion approach using a mid-infrared pump source. We used a 3.3 {\mu}m dual-chirped optical parametric amplification source…
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…
High energy terahertz pulses are produced by optical rectification (OR) in organic crystals DAST and DSTMS by a Ti:sapphire amplifier system centered at 0.8 microns. The simple scheme provides broadband spectra between 1 and 5 THz, when…
We report the Terahertz optical properties of the Vanadium doped [100] \b{eta}-Ga2O3 using Terahertz Time-Domain Spectroscopy (THz-TDS). The V-doped \b{eta}-Ga2O3 crystal shows strong birefringence in the 0.2-2.4 THz range. Further, phase…
We demonstrate a data mining approach to discover and develop new organic nonlinear optical crystals that produce intense pulses of terahertz radiation. We mine the Cambridge Structural Database for non-centrosymmetric materials and use…
We introduce a general technique to generate compressed broadband terahertz pulses based on difference frequency generation of optical pump radiation using aperiodically poled structures. The pump pulse format and poling of the crystals…
Birefringence ($\Delta n$) is the dependence of the refractive index of a material on the polarization of light travelling through it. Birefringent materials are used as polarizers, waveplates, and for novel light-matter coupling. While…