Mapping multiple photonic qubits into and out of one solid - state atomic ensemble USMANI

The future challenge of quantum communication is scalable quantum networks, which require coherent and reversible mapping of photonic qubits onto atomic systems (quantum memories). A crucial requirement for realistic networks is the ability to effi ciently store multiple qubits in one quantum memory. In this study, we show a coherent and reversible mapping of 64 optical modes at the single-photon level in the time domain onto one solid-state ensemble of rare-earth ions. Our light – matter interface is based on a high-bandwidth (100 MHz) atomic frequency comb, with a predetermined storage time of >~ 1 μs. We can then encode many qubits in short ( < 10 ns) temporal modes (time-bin qubits). We show the good coherence of mapping by simultaneously storing and analysing multiple time-bin qubits. USMANI, Imam, et al. Mapping multiple photonic qubits into and out of one solid-state atomic ensemble. Nature Communications, 2010, p. 1-7 DOI : 10.1038/ncomms1010