We present a new type of streak camera to measure the temporal shape of pul
ses in the extreme ultraviolet (XUV) region: A cloud of noble gas atoms is
used as a photocathode. The first results at 57 nm show a time resolution o
f 10 ps. Modifications to improve the time resolution are discussed. Using
a noble gas as a photocathode has the potential to decrease the temporal re
solution of the streak camera in the XUV to less than 0.5 ps. (C) 2001 Amer
ican Institute of Physics.