X-ray streak camera temporal resolution improvement using a longitudinal time-dependent field

X-ray streak cameras (XSC) have been known to be one of the fastest detectors for ultrafast X-ray science. A number of applications in material science, biochemistry, accelerator physics, require sub-picosecond resolution to study new phenomena. In this paper, we report on a new method which can potentially improve the temporal resolution of a streak camera down to 100 fs. This method uses a time-dependent acceleration field to lengthen the photoelectron bunch, improving the time resolution as well as reducing the time dispersion caused by initial energy spread and the effects from the space charge forces. A computer simulation of an XSC using this method shows significant improvement in the resolution.