Hamburg 2009 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

Q: Fachverband Quantenoptik und Photonik

Q 58: Quanteninformation: Atome und Ionen III

Q 58.1: Talk

Friday, March 6, 2009, 10:30–10:45, VMP 6 HS-A

a millisecond quantum memory for scalable quantum networks — •bo zhao¹, yuao chen^1,2, xiaohun bao^1,2, thorsten strassel¹, chihsung chuu¹, xianmin jin², jörg schmiedmayer³, zhensheng yuan^1,2, shuai chen¹, and jianwei pan^1,2 — ¹Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Philosophenweg 12, 69120 Heidelberg, Germany — ²Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China Hefei, Anhui 230026, China — ³Atominstitut derösterreichischen Universitäten, TU-Wien, A-1020 Vienna Austria

Scalable quantum information processing critically depends on the capability of storage of a quantum state. Although atomic memories for classical lights and continuous variables have been demonstrated with milliseconds storage time, there is no equal advance in the development of quantum memory for single excitations, where only around 10 µs storage time was achieved. Here we report our experimental investigations on extending the storage time of quantum memory for single excitations. We isolate and identify distinct mechanisms for the decoherence of spin wave in atomic ensemble quantum memories. By exploiting the magnetic field insensitive state, "clock state", and generating a long-wavelength spin wave to suppress the dephasing, we succeed in extending the storage time of the quantum memory to 1 ms. Our result represents a substantial progress towards long-distance quantum communication and enables a realistic avenue for large scale quantum information processing.