  The realization of quantum memory using warm atomic vapor cells is appealing
because of their commercial availability and the perceived reduction in
experimental complexity. In spite of the ambiguous results reported in the
literature, we demonstrate that quantum memory can be implemented in a single
cell with buffer gas using the geometry where the write and read beams are
nearly co-propagating. The emitted Stokes and anti-Stokes photons display
cross-correlation values greater than 2, characteristic of quantum states, for
delay times up to 4 microseconds.
