Notes

Nonadiabatic quantum character from the clear enthusiastic state intramolecular proton change in 10-hydroxybenzo[h]quinoline.
The vector vortex light beam, which exhibits a space-variant polarization state and is coupled with orbital angular momentum of light, has been drawing much attention due to its fundamental interest and potential applications in a wide range. Here we reveal both theoretically and experimentally that a diffractive structure having cylindrical symmetry is shown to be transparent for the vector vortex state of light with arbitrary topology. We demonstrate such an intriguing phenomenon in the Fresnel diffraction condition, where the vector Helmholtz wave equation can be utilized in the paraxial regime. Our demonstration has implications in control and manipulation of vector vortex light beams in diffractive optics, and hence, it may find potential applications.We propose a Babinet-invertible chiral metasurface for achieving dynamically reversible and strong circular dichroism (CD). The proposed metasurface is composed of a VO2-metal hybrid structure, and when VO2 transits between the dielectric state and the metallic state, the metasurface unit cell switches between complementary structures that are designed according to Babinet's principle. This leads to a large and reversible CD tuning range between ±0.5 at 0.97 THz, which is larger than the one found in the literature. We attribute the CD effect to extrinsic chirality of the proposed metasurface. We envision that the Babinet-invertible chiral metasurface proposed here will advance the engineering of active and tunable chiro-optical devices and promote their applications.For the first time, to the best of our knowledge, we experimentally observed a novel quasi-coherent noise-like pulse (NLP) in a simplified nonlinear polarization evolution mode-locking fiber laser when appropriate polarization was maintained for the lasing light through a three-dimensional rotatable polarization beam splitter inside the cavity. The degree of first-order coherence was evaluated after an interferogram measurement. The evolution of the measured shot-to-shot spectrum revealed that the NLPs possess quasi-coherence. https://www.selleckchem.com/ Self-starting ultrafast soliton pulses switching to quasi-coherent NLPs at higher pump power levels were due to the preservation of the soliton features, mainly the Kelly sidebands in the spectrum. Quasi-coherent NLPs with average power of 56.58 mW and 10.4% slope efficiency were achieved with single pulse energy of 3.22 nJ.Temperature-induced redshift of the V-O charge transfer band edge and the temperature quenching effect were combined for designing ratiometric optical thermometry. Following this approach, opposite thermal behaviors of Tm3+ and Eu3+ emissions were realized in the range of 300 to 380 K in Tm3+/Eu3+ co-doped YVO4. Applying the temperature dependent fluorescence intensity ratio of Eu3+ to Tm3+ as temperature readout, the maximal relative sensitivity reaches up to 4.6%K-1 around 330 K. This result makes our proposed strategy an excellent candidate for developing high-sensitivity optical thermometry.We reported a high-power pure Kerr-lens mode-locked YbCALYO laser based on the dual-confocal cavity delivering sub-100-fs pulses. The output pulses at 81 MHz have an average power of 10.4 W and the pulse duration of 98 fs, corresponding to the peak power of 1.14 MW. This is, to the best of our knowledge, the highest average power ever reported for a Kerr-lens mode-locked Yb-bulk oscillator. Analysis of the dual-confocal cavity was also conducted, which indicates a way to achieve higher average power. We believe the result described in this Letter may pave a way to develop Kerr-lens mode-locked bulk lasers with much higher average power.In recent years, the need for a high-power laser has been of great interest for different applications, including direct-laser processing, light detection, medicine, and lighting. However, high-power lasers with high intensities give rise to fundamental problems for optical detectors and imaging systems with low threshold damage, which still need reliable solutions. Here we report and numerically demonstrate a hybrid system that synergistically combines a broadband OPL with a transmittance difference between on-state (70°C) and off-state (25°C) about 62.5%, and a diffraction-limited broadband metalens from 1534 to 1664 nm. Such a metalens power limiter could be used in any system requiring an intermediate focal plane in the optical path to the detector from damage by exposure to high-intensity lasers.Most of the saturable absorbers commonly used to perform mode locking in laser cavities affect the trigger conditions of laser oscillation, which requires manually forcing the laser start-up by various means such as polarization controllers. We present a procedure for designing a laser cavity driven by a nonlinear optical loop mirror, which allows the laser to operate optimally without interfering with the oscillation triggering conditions, thus opening up possibilities for integration of this type of laser.Isolated attosecond pulses are useful to perform pump-probe experiments at a high temporal resolution, and provide a new tool for ultrafast metrology. However, it is still a challenging task to generate such pulses of high intensity, even for a few-cycle laser. Through particle-in-cell simulations, we show that it is possible to directly generate a giant isolated attosecond pulse in the transmission direction from relativistic laser-driven plasmas. Compared to attosecond pulse generation in the reflection direction, no further spectral filtering is needed. The underlying radiation mechanism is coherent synchrotron emission, and the transmitted isolated attosecond pulse can reach relativistic intensity. This provides a promising alternative to generate intense isolated attosecond pulses for ultrafast studies.The nonlinear Talbot effect has sparked considerable interest of researchers since it was proposed in recent years because it has many advantages compared with the Talbot effect in linear optics. In previous researches, such a nonlinear Talbot effect is only observed in nonlinear photonic crystals, which cannot dynamically manipulate in real time. Here, we report and experimentally demonstrate the high efficiency and dynamic manipulation of such a nonlinear Talbot effect with structured light. Different from the previous scheme, the nonlinear self-imaging effect observed in our experiment originates from the spatial phase structure of the incident fundamental frequency light. In our experiments, integer and fractional second-harmonic Talbot self-imaging is observed. Our results not only extend a novel technique for dynamic manipulation of the nonlinear Talbot effects, but also may have potential applications in parallel optical lithography, optical imaging, and optical computing.
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