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arXiv · 0908.2309

Demonstration of atomic frequency comb memory for light with spin-wave storage

Mikael Afzelius·Imam Usmani·Atia Amari·Björn Lauritzen·Andreas Walther·Christoph Simon·Nicolas Sangouard·Jiří Minář·Hugues de Riedmatten·Nicolas Gisin·Stefan Kröll
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Abstract

We present a light-storage experiment in a praseodymium-doped crystal where the light is mapped onto an inhomogeneously broadened optical transition shaped into an atomic frequency comb. After absorption of the light the optical excitation is converted into a spin-wave excitation by a control pulse. A second control pulse reads the memory (on-demand) by reconverting the spin-wave excitation to an optical one, where the comb structure causes a photon-echo type rephasing of the dipole moments and directional retrieval of the light. This combination of photon echo and spin-wave storage allows us to store sub-microsecond (450ns) pulses for up to 20 microseconds. The scheme has a high potential for storing multiple temporal modes in the single photon regime, which is an important resource for future long-distance quantum communication based on quantum repeaters.

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Mikael Afzelius, Imam Usmani, Atia Amari, Björn Lauritzen, Andreas Walther, Christoph Simon, Nicolas Sangouard, Jiří Minář, Hugues de Riedmatten, Nicolas Gisin, Stefan Kröll. 2010-02-11. Demonstration of atomic frequency comb memory for light with spin-wave storage. https://doi.org/10.1103/physrevlett.104.040503

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