相关论文: Universality in odd-even harmonic generation and a…
We investigate the process of circularly polarized high harmonic generation in molecules using a bicircular laser field. In this context, we show that molecules offer a very robust framework for the production of circularly polarized…
We report a plasma-based strong THz source generated by using intense femtosecond laser pulses to irradiate solid targets at relativistic intensity >10^18W/cm2. Energies up to 50 microJ/sr per THz pulse is observed in the specular direction…
We investigate the photon emission in coupled quantum dots based on symmetry considerations. With the help of a new theorem we proved, we reveal the origin of the various emission patterns, which is the combinative symmetry in the time…
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…
High-order harmonic generation in the presence of a chirped THz pulse is investigated numerically with a complete 3D non-adiabatic model. The assisting THz pulse illuminates the HHG gas cell laterally inducing quasi-phase-matching. We…
The interaction of intense laser pulses with plasma mirrors has demonstrated the ability to generate high-order harmonics, producing a bright source of extreme ultraviolet (XUV) radiation and attosecond pulses. Here, we report an unexpected…
Anomalously high generation efficiency of coherent higher field-harmonics in collisions between {\em oppositely charged particles} in the field of femtosecond lasers is predicted. This is based on rigorous numerical solutions of a quantum…
High-order harmonics are ubiquitous in nature and present in electromagnetic, acoustic, and gravitational waves. They are generated by periodic nonlinear processes or periodic high-frequency pulses. However, this periodicity is often…
Second-harmonic emission at a frequency that is twice the laser frequency is an important diagnostic for nonlinear laser-plasma interaction. It is forbidden for centrosymmetric materials such as the bulk of sapphire. The symmetry, however,…
We present a universal and rigorous approach to study difference frequency generation in the terahertz domain, keeping the number of degrees of freedom to a minimum, through the definition of a suitable figure of merit. The proposed method…
In our earlier work on harmonic generation with complex light [Nature Communications 15, 6878 (2024)], we demonstrated how the harmonic spectrum of a complex laser beam in a nonlinear medium can be obtained through the judicious application…
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 have applied harmonic expansion to derive an analytical solution for the Lorenz-Haken equations. This method is used to describe the regular and periodic self-pulsing regime of the single mode homogeneously broadened laser. These…
High-order harmonic generation via single-slit diffraction of relativistic laser pulses is investigated. Using fully kinetic 2D and 3D particle-in-cell simulations, we show that interesting optical phenomena emerge, including the generation…
We derive simple formulas to explain terahertz (THz) emission from semiconductor surfaces excited by a femtosecond (fs) laser. Femtosecond optical pulses with energies larger than the bandgap create photocarriers which travel and generate…
We consider the nonlinear terahertz emission by the system of cavity polaritons in the regime of polariton lasing. To account for the quantum nature of terahertz-polariton coupling we use the Lindblad master equation approach and…
High-power multi-color terahertz (THz) radiation exhibits extraordinary scientific application prospects at various scientific frontiers, for its capacity to deliver THz excitation at multiple frequencies simultaneously. However, the…
The interaction of intense mid-infrared laser fields with atoms and molecules leads to a range of new opportunities, from the production of bright, coherent radiation in the soft x-ray range to imaging molecular structures and dynamics with…
The two-color laser field scheme for broad-band terahertz (THz) radiation from air has been intensively and broadly investigated due to the simplicity in technology and relative high yield efficiency. Experiments showed that the detected…
Near-field imaging with terahertz (THz) waves is emerging as a powerful technique for fundamental research in photonics and across physical and life sciences. Spatial resolution beyond the diffraction limit can be achieved by collecting THz…