Observation of Gigawatt-Class THz Pulses from a Compact Laser-Driven Particle Accelerator

Abstract

We report the observation of subpicosecond terahertz (T-ray) pulses with energies ≥460 μJ from a laser-driven ion accelerator, thus rendering the peak power of the source higher even than that of state-of-the-art synchrotrons. Experiments were performed with intense laser pulses (up to 5×10(19) W/cm(2)) to irradiate thin metal foil targets. Ion spectra measured simultaneously showed a square law dependence of the T-ray yield on particle number. Two-dimensional particle-in-cell simulations show the presence of transient currents at the target rear surface which could be responsible for the strong T-ray emission.

High field terahertz emission from relativistic laser-driven plasma wakefields

“…6 Besides, high field THz source can be generated from relativistic laser irradiated plasmas via various mechanisms. [7][8][9][10] In our previous work, we have shown numerically that THz pulses with field strength > GV/cm can be generated in plasma wakefieds by use of temporally tailored laser pulses. 11 The mechanism is related to the excitation of transverse plasma current via electron residual momentum left by the temporally tailored laser pulse.…”

Demonstration of a low-frequency three-dimensional terahertz bullet with extreme brightness

“…Although the former has been ahead in terms of intensity, the availability and versatility of lasers are dominating time-resolved THz high-field science. The most prominent techniques for intense THz pulse generation, by employing a femtosecond amplified laser pulse, are based on laser-driven ion acceleration 16 , emission from a gas plasma 17 and optical rectification in inorganic (for example, LiNbO 3 ) 18 and organic nonlinear crystals (for example, 2-(3-(4-hydroxystyryl)-5,5-dimethylcyclohex-2-enylidene)malononitrile) (OH1), 4-N,N-dimethylamino-4 0 -N 0 -methyl-stilbazolium tosylate (DAST), 4-N,N-dimethylamino-4 0 -N 0 -methyl-stilbazolium 2,4,6-trimethylbenzenesulfonate (DSTMS)) [19][20][21] . So far, the peak fields from these systems have been limited to 0.12-0.5 GV m À 1 .…”

Effects of target pre-heating and expansion on terahertz radiation production from intense laser-solid interactions

“…It therefore appears that the contribution of THz emission due to this mechanism is less important. As discussed above, other THz generation mechanisms are associated with energetic electron production, such as the surface transient current at the front [3] or rear [22] , antenna emission [2] , and transient radiation [23][24][25] , which occur when the preplasma has moderate-to-short density scale lengths. Generally, all of these mechanisms depend upon the preplasma conditions in two ways, by changing (1) the absorption of laser energy to fast electrons, and (2) the injection properties of the fastelectron distribution (see reference [26] for an example study of the sensitivity to preplasma scale length).…”