We produce a 600-ns pulse of 1.86-dB squeezed vacuum at 795 nm in an optical
parametric amplifier and store it in a rubidium vapor cell for 1 us using
electromagnetically induced transparency. The recovered pulse, analyzed using
time-domain homodyne tomography, exhibits up to 0.21+-0.04 dB of squeezing. We
identify the factors leading to the degradation of squeezing and investigate
the phase evolution of the atomic coherence during the storage interval.Comment: To appear in PRL. Changes to version 3: we present a larger data set
featuring somewhat less squeezing, but also better statistics and a lower
margin of error. Some additional revisions are made in response to the
referees' comment
