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Related papers: Control of $\text{N}_2^+$ Air Lasing

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Cavity-free lasing in atmospheric air has stimulated intense research towards fundamental understanding of underlying physical mechanisms. In this Letter, we identify a new mechanism -- third harmonic photon mediated resonant energy…

The interaction of a short, few-cycle light pulse and an atom which is prepared initially in a superposition of two stationary states is shown to exhibit strong signatures of atomic coherence. For a given waveform of the laser pulse,…

Atomic Physics · Physics 2017-01-04 Viktor Ayadi , Mihaly G. Benedict , Peter Dombi , Peter Foldi

We demonstrate that quantum Lyapunov control provides an effective strategy for enhancing superconducting correlations in the Fermi-Hubbard model without requiring careful parameter tuning. While photoinduced superconductivity is sensitive…

Quantum Physics · Physics 2025-09-30 Oleksandr Povitchan , Denys I. Bondar , Andrii G. Sotnikov

An intense femtosecond-laser excitation of a solid induces highly nonthermal conditions. In materials like silicon, laser-induced bond-softening leads to a highly incoherent ionic motion and eventually nonthermal melting. But is this…

Materials Science · Physics 2025-08-07 Tobias Zier , Eeuwe S. Zijlstra , Martin E. Garcia , David A. Strubbe

The directional control of molecular dissociation with the laser electric field waveform is a paradigm and was demonstrated for a variety of molecules. In most cases, the directional control occurs via a dissociative ionization pathway. The…

High resolution Fourier transform spectroscopy and Laser induced fluorescence has been performed on LiCa in the infrared spectral range. We analyze rovibrational transitions of the $(2)^2\Sigma^+$--$X(1)^2\Sigma^+$ system of LiCa and find…

Chemical Physics · Physics 2022-09-19 J. Gerschmann , E. Schwanke , S. Ospelkaus , E. Tiemann

Intense femtosecond laser pulses interacting with solids can drive electrons to relativistic energies, enabling miniaturized particle accelerators and bright extreme-ultraviolet light sources. In-situ space-time control of these electrons…

Plasma Physics · Physics 2024-11-27 Ankit Dulat , Sk Rakeeb , Sagar Dam , Amit D. Lad , Yash M. Ved , Sergey Kruk , G. Ravindra Kumar

We explore coherent control of stimulated Raman scattering in the nonimpulsive regime. Optical pulse shaping of the coherent pump field leads to control over the stimulated Raman output. A model of the control mechanism is investigated.

Quantum Physics · Physics 2009-11-10 B. J. Pearson , P. H. Bucksbaum

We present measurements on pulsed four-wave mixing involving a Rydberg state in an atomic vapor cell. The excitation to the Rydberg state is conducted by a pulsed two-photon excitation on the nanosecond timescale that is combined with a…

Atomic Physics · Physics 2015-06-23 B. Huber , A. Kölle , T. Pfau

The effect of collectivity on the loading of an atom laser via optical pumping is discussed. In our model, atoms in a beam are laser-excited and subsequently spontaneously decay into a trapping state. We consider the case of sufficiently…

Atomic Physics · Physics 2015-05-14 M. A. Macovei , J. Evers

We report a systematic investigation into the processes behind a near hundredfold enhanced second harmonic wave generated from a laser-induced air plasma, by examining the temporal dynamics of the frequency conversion processes, and the…

In attosecond streaking, an electron is released by a short xuv pulse into a strong near infrared laser field. When the laser coupling between two states in the target is weak relative to the detuning, the streaking technique, which allows…

Atomic Physics · Physics 2015-05-19 Jan Conrad Baggesen , Lars Bojer Madsen

The implementation of a superradiant laser as an active frequency standard is predicted to provide better short-term stability and robustness to thermal and mechanical fluctuations when compared to standard passive optical clocks. However,…

Quantum Physics · Physics 2023-11-06 Anna Bychek , Helmut Ritsch

Photoinduced phase transitions from insulating to metallic states, accompanied by structural re-arrangements, have been recently reported in complex transition-metal oxides. However, the optical control of a purely electronic phase…

We disclose an unanticipated link between plasmonics and nonlinear frequency down-conversion in laser-induced gas-plasmas. For two-color femtosecond pump pulses, a plasmonic resonance is shown to broaden the terahertz emission spectra…

We examine a regime in which a linearly-polarized laser pulse with relativistic intensity irradiates a sub-critical plasma for much longer than the characteristic electron response time. A steady-state channel is formed in the plasma in…

Plasma Physics · Physics 2016-05-25 A. V. Arefiev , V. N. Khudik , A. P. L. Robinson , G. Shvets , L. Willingale , M. Schollmeier

Ultra-intense laser-matter interaction experiments (>10$^{18}$ W/cm$^{2}$) with dense targets are highly sensitive to the effect of laser "noise" (in the form of pre-pulses) preceding the main ultra-intense pulse. These system-dependent…

Instrumentation and Detectors · Physics 2015-06-22 S. Feister , J. A. Nees , J. T. Morrison , K. D. Frische , C. Orban , E. A. Chowdhury , W. M. Roquemore

We present a simple approach allowing to obtain analytical expressions for laser pulses that can drive a two-level system in an arbitrarily chosen way. The proposed scheme relates every desired population-evolution path to a single resonant…

Quantum Physics · Physics 2015-02-18 Nikolay V. Golubev , Alexander I. Kuleff

Attosecond transient absorption spectroscopy (ATAS) is becoming an indispensable and powerful tool in the emerging field of attochemistry, while the interpretation of measurements often requires full considerations of the coupling among…

The temporal dynamics of double ionization of H2 has been investigated both experimentally and theoretically with few-cycle laser pulses. The main observables are the proton spectra associated to the H^+ + H^+ fragmentation channel. The…

Quantum Physics · Physics 2008-09-23 Sébastien Saugout , Eric Charron , Christian Cornaggia