  A cold atomic ensemble suits well for optical quantum memories, and its
entanglement with a single photon forms the building block for quantum networks
that give promise for many revolutionary applications. Efficiency and lifetime
are among the most important figures of merit for a memory. In this paper, we
report the realization of entanglement between an atomic ensemble and a
single-photon with subsecond lifetime and high efficiency. We engineer dual
control modes in a ring cavity to create entanglement and make use of
3-dimensional optical lattice to prolong memory lifetime. The memory efficiency
is 38% for 0.1 second storage. We verify the atom-photon entanglement after 1
second storage by testing the Bell inequality with a result of $S=2.36\pm0.14$.
