Efficient and long-lived quantum memory with cold atoms inside a ring cavity
arXiv:1207.2894 · doi:10.1038/nphys2324
Abstract
Quantum memories are regarded as one of the fundamental building blocks of linear-optical quantum computation and long-distance quantum communication. A long standing goal to realize scalable quantum information processing is to build a long-lived and efficient quantum memory. There have been significant efforts distributed towards this goal. However, either efficient but short-lived or long-lived but inefficient quantum memories have been demonstrated so far. Here we report a high-performance quantum memory in which long lifetime and high retrieval efficiency meet for the first time. By placing a ring cavity around an atomic ensemble, employing a pair of clock states, creating a long-wavelength spin wave, and arranging the setup in the gravitational direction, we realize a quantum memory with an intrinsic spin wave to photon conversion efficiency of 73(2)% together with a storage lifetime of 3.2(1) ms. This realization provides an essential tool towards scalable linear-optical quantum information processing.
6 pages, 4 figures
References in corpus (13)
- The Quantum Internet
- Quantum teleportation between light and matter
- Resource-efficient linear optical quantum computation
- Quantum Storage of Photonic Entanglement in a Crystal
- Experimental demonstration of a BDCZ quantum repeater node
- A Single-Atom Quantum Memory
- A millisecond quantum memory for scalable quantum networks
- How good must single photon sources and detectors be for efficient linear optical quantum computation?
- Photon storage in Lambda-type optically dense atomic media. I. Cavity model
- Interfacing Collective Atomic Excitations and Single Photons
- Robust and Efficient Quantum Repeaters with Atomic Ensembles and Linear Optics
- Deterministic single photons via conditional quantum evolution
- Scalable Generation of Graph-State Entanglement through Realistic Linear Optics