We propose a photon echo quantum memory scheme using detuned Raman coupling to long-lived ground states. In contrast to previous three-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 vapor 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.
© 2008 Optical Society of America
Original Manuscript: June 27, 2008
Manuscript Accepted: July 24, 2008
Published: October 10, 2008
G. Hétet, M. Hosseini, B. M. Sparkes, D. Oblak, P. K. Lam, and B. C. Buchler, "Photon echoes generated by reversing magnetic field gradients in a rubidium vapor," Opt. Lett. 33, 2323-2325 (2008)