  We propose an original quantum memory protocol. It belongs to the class of
rephasing processes and is closely related to two-pulse photon echo. It is
known that the strong population inversion produced by the rephasing pulse
prevents the plain two-pulse photon echo from serving as a quantum memory
scheme. Indeed gain and spontaneous emission generate prohibitive noise. A
second $\pi$-pulse can be used to simultaneously reverse the atomic phase and
bring the atoms back into the ground state. Then a secondary echo is radiated
from a non-inverted medium, avoiding contamination by gain and spontaneous
emission noise. However, one must kill the primary echo, in order to preserve
all the information for the secondary signal. In the present work, spatial
phase mismatching is used to silence the standard two-pulse echo. An
experimental demonstration is presented.
