Communications Physics (Jun 2023)

Fast, noise-free atomic optical memory with 35-percent end-to-end efficiency

  • Omri Davidson,
  • Ohad Yogev,
  • Eilon Poem,
  • Ofer Firstenberg

DOI
https://doi.org/10.1038/s42005-023-01247-4
Journal volume & issue
Vol. 6, no. 1
pp. 1 – 6

Abstract

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Abstract Coherent optical memories will likely play an important role in future quantum communication networks. Among the different platforms, memories based on ladder-type orbital transitions in atomic gasses offer high bandwidth (>100 MHz), continuous (on-demand) readout, and low-noise operation. Here we report on an upgraded setup of our previously-reported fast ladder memory, with improved efficiency and lifetime, and reduced noise. The upgrade employs a stronger control field, wider signal beam, reduced atomic density, higher optical depth, annular optical-pumping beam, and weak dressing of an auxiliary orbital to counteract residual Doppler-broadening. For a 2 ns-long pulse, we demonstrate 53% internal efficiency, 35% end-to-end efficiency, 3 × 10−5 noise photons per pulse, and a 1/e lifetime of 108 ns. This combination of performances is a record for continuous-readout memories.