Temporal Variation of Cross-Shore Bottom Profile along an Observational Pier at Joetsu-Ogata Coast

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Numerical Investigation on Effects of a Diversion Channel along a Meandering River Based on a 2D Model

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Debris-Flow Deposition and Erosion Processes of the Sediment Deposit Upstream of a Check Dam

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Transient Slope Stability Analysis of Landslide Dam Failure

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Generation of wavelength-tunable few-cycle pulses in the mid-infrared at repetition rates up to 10 kHz

We demonstrate a compact and tunable mid-infrared light source that provides carrier-envelope-phase (CEP)-locked pulses at repetition rates from 500 Hz to 10 kHz. The seed pulses were generated by intra-pulse difference frequency mixing of the output of an Yb:KGW regenerative amplifier that had been spectrally broadened by continuum generation using multiple plates. Then, a two-stage optical parametric amplifier was used to obtain output energies of about 100 µJ/pulse for center wavelengths between 2.8 and 3.5 µm. Owing to the intense pulse energies, it was possible to compress the multi-cycle pulses down to two-cycle pulses using YAG and Si plates

Interference effects in high-order harmonics from colloidal perovskite nanocrystals excited by an elliptically polarized laser

Halide perovskite nanocrystals are suitable materials for photonic devices because their highly efficient luminescence can be tuned over a wide wavelength range by changing the nanocrystal composition and size. Here, we report on the high-order harmonic generation in a solution-processed perovskite CsPbBr₃ nanocrystal film that is excited by a strong midinfrared laser. We observe harmonics up to the 13th order, which is ultraviolet light well above the band-gap energy. By using elliptically polarized laser light, we analyze the influence of the sample structure on the intensity of the 5th harmonic. It is also found that the randomness in the orientation of the nanocrystals in the film induces a reduction in the harmonic intensities due to the interference among the harmonics emitted from nanocrystals with different phases. Our observation of high-order harmonics from nanocrystal films opens a way towards the development of an intensity modulator that can be tuned simply by changing the excitation ellipticity