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تسجيل مستخدم جديدTicking terahertz wave generation in attoseconds
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We perform a joint measurement of terahertz waves and high-order harmonics generated from noble atoms driven by a fundamental laser pulse and its second harmonic. By correlating their dependence on the phase-delay of the two pulses, we determine the generation of THz waves in tens of attoseconds precision. Compared with simulations and models, we find that the laser-assisted soft-collision of the electron wave packet with the atomic core plays a key role. It is demonstrated that the rescattering process, being indispensable in HHG processes, dominant THz wave generation as well but in a more elaborate way. The new finding might be helpful for the full characterization of the rescattering dynamics.
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The Terahertz or millimeter wave frequency band (300 GHz - 3 THz) is spectrally located between microwaves and infrared light and has attracted significant interest for applications in broadband wireless communications, space-borne radiometers for Ea
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High-order harmonic generation by few-cycle 800 nm laser pulses in neon gas in the presence of a strong terahertz (THz) field is investigated numerically with propagation effects taken into account. Our calculations show that the combination of THz f
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We present the experimental and theoretical details of our recent published letter [Phys. Rev. Lett. 115. 123002] on synchronized high-harmonic and terahertz-wave spectroscopy (HATS) from nonadiabatically aligned nitrogen molecules in dual-color lase
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We investigate the generation of broadband terahertz (THz) pulses with phase singularity from air plasmas created by fundamental and second harmonic laser pulses. We show that when the second harmonic beam carries a vortex charge, the THz beam acquir
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There are many different types of time keeping devices. We use the phrase ticking clock to describe those which -- simply put -- tick at approximately regular intervals. Various important results have been derived for ticking clocks, and more are in
the pipeline. It is thus important to understand the underlying models on which these results are founded. The aim of this paper is to introduce a new ticking clock model from axiomatic principles that overcomes concerns in the community about the physicality of the assumptions made in previous models. The ticking clock model in [arXiv:1806.00491] achieves high accuracy, yet lacks the autonomy of the less accurate model in [10.1103/PhysRevX.7.031022]. Importantly, the model we introduce here achieves the best of both models: it retains the autonomy of [10.1103/PhysRevX.7.031022] while allowing for the high accuracies of [arXiv:1806.00491]. What is more, [10.1103/PhysRevX.7.031022] is revealed to be a special case of the new ticking clock model.
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