2026-10-12T10:50:04Z https://www.scidb.cn/oai

10.57760/sciencedb.13978 2023-12-11T10:00:22Z

2023-12-11 Strong double space-time wave packets using optical parametric amplification doi:10.57760/sciencedb.13978 en The space-time (ST) wave packet, a type of light source with many anomalous behaviors, has already found application in weak-field optics, however its generation method limits its energy and therefore its application in strong-field optics. Here we show that the type-I collinear optical parametric amplification (OPA) is a natural amplifier for a ST wave packet, because in it, the ST spectrum (i.e., angle-dependent phase-matching spectrum) of the signal and idler has the same analytical expression as that of a ST wave packet under the narrowband approximation. The high gain in a thin-crystal OPA allows for large energy amplification while ensuring unchanged ST correlation. Meanwhile, a double ST wave packet containing two collinear-propagating ones of the amplified signal and the generated idler via the nondegenerate OPA is reported, which with short- and long-wavelengths (relative to the degenerate-wavelength) have superluminal and subluminal velocities, respectively. This study realizes energy amplification, wavelength conversion, and velocity switching of a ST wave packet and will expand its application in many fields. optical; parametric amplification; space-time Zhaoyang Li Yuxin Leng Ruxin Li RESTRICTED dataset http://www.doi.org/10.1038/s42005-022-01085-w Science Data Bank