Dispersion requirements in coherent frequency-to-time mapping

摘要

The frequency-to-time mapping technique (also known as thetemporal far-field phenomenon) usually requires a significant amount ofdispersion to stretch an ultrashort optical pulse so that the intensity profilebecomes a scaled replica of its optical spectrum. In this work, we study thenear-to-far-field transition and find that the far-field condition can berelaxed in some cases relevant for radio-frequency (RF) waveformgeneration. This observation has allowed us to achieve intensity signalswith an ultrabroad RF bandwidth content