  Random access memory is an indispensable device for classical information
technology. Analog to this, for quantum information technology, it is desirable
to have a random access quantum memory with many memory cells and programmable
access to each cell. We report an experiment that realizes a random access
quantum memory of 105 qubits carried by 210 memory cells in a macroscopic
atomic ensemble. We demonstrate storage of optical qubits into these memory
cells and their read-out at programmable times by arbitrary orders with
fidelities exceeding any classical bound. Experimental realization of a random
access quantum memory with many memory cells and programmable control of its
write-in and read-out makes an important step for its application in quantum
communication, networking, and computation.
