Real-time shot-noise-limited differential photodetection for atomic quantum control.

  title={Real-time shot-noise-limited differential photodetection for atomic quantum control.},
  author={F. Martin Ciurana and Giorgio Colangelo and Robert J. Sewell and Morgan W. Mitchell},
  journal={Optics letters},
  volume={41 13},
We demonstrate high-efficiency, shot-noise-limited differential photodetection with real-time signal conditioning, suitable for feedback-based quantum control of atomic systems. The detector system has quantum efficiency of 0.92, is shot-noise-limited from 7.4×105 to 3.7×108 photons per pulse, and provides real-time voltage-encoded output at up to 2.3 M pulses per second. 

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