Broadband THz emission from gas plasmas induced by femtosecond optical pulses: From fundamentals to applications

Abstract

We review the generation of broadband THz radiation from femtosecond photo-induced gas plasmas, with an emphasis on the highly efficient "AC-bias" case where the plasma is generated and driven by a superposition of fundamental and second-harmonic optical fields. The dependence on experimental parameters such as pulse energy, air pressure, polarization and focusing are presented, and compared to the predictions from semi-quantitative models for the THz generation process, namely (i) a microscopic photocurrent model and (ii) a fourwave mixing model. We also employ these models to the case of few-cycle pulses, where the observed THz emission is related directly to the carrier-envelope phase of the pulses, and hence provides a mechanism with which to measure this phase. +THz generation in a photoinduced plasma using both fundamental and second-harmonic optical fields.

Giant tunable Faraday effect in a semiconductor magneto-plasma for broadband terahertz polarization optics

“…1(a) [21]. Coherent THz pulses were generated from a nitrogen gas plasma [22] created by focusing both the fundamental and the second harmonic wave of the output of a chirpedpulse amplifier (CPA-2001, Clark-MXR, Inc) with a center wavelength of 775 nm, a pulse width of ~150 fs, a pulse energy of ~600 µJ, and a repetition rate of 1 kHz. A β-barium borate (BBO) crystal was placed between the lens (f = 10 cm) and the focus position.…”

Генерация Предельно-Коротких Импульсов При Возбуждении Нелинейной Резонансной Среды Световым Зайчиком, Движущимся Со Сверхсветовой Скоростью

“…Поэтому генерируемое излучение может лежать в терагерцовой или ИК области спектра. Таким образом, предложенный метод может служить еще одним методом генерации THz излучения, способы получения которого активно изучаются на се-годняшний день [48][49][50][51].…”

Thermal Lensing Compensation in the Development of 30 fs Pulse Duration Chirped Pulse Amplification Laser System and Single-Shot Intensity-Phase Measurement

“…Such high peak power laser systems are used to study high harmonics generation, white light continuum generation, plasma and optical field ionization [12][13][14]. A rapid advancement in the development of high-average-peak power CPA laser systems [11,[14][15][16] has been observed in recent years. However, many technical issues related to development and characterization needs to be addressed.…”