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arXiv · 0806.4258

Photon echoes generated by reversing magnetic field gradients in a rubidium vapour

G. Hétet·M. Hosseini·B. M. Sparkes·D. Oblak·P. K. Lam·B. C. Buchler
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Abstract

We propose a photon echo quantum memory scheme using detuned Raman coupling to long lived ground states. In contrast to previous 3-level schemes based on controlled reversible inhomogeneous broadening that use sequences of $π$-pulses, the scheme does not require accurate control of the coupling dynamics to the ground states. We present a proof of principle experimental realization of our proposal using rubidium atoms in a warm vapour cell. The Raman resonance line is broadened using a magnetic field that varies linearly along the direction of light propagation. Inverting the magnetic field gradient rephases the atomic dipoles and re-emits the light pulse in the forward direction.

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G. Hétet, M. Hosseini, B. M. Sparkes, D. Oblak, P. K. Lam, B. C. Buchler. 2008-08-06. Photon echoes generated by reversing magnetic field gradients in a rubidium vapour. https://doi.org/10.1364/ol.33.002323

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