  Methods borrowed from the world of quantum information processing have lately
been used to enhance the signal-to-noise ratio of quantum detectors. Here we
analyze the use of stabilizer quantum error-correction codes for the purpose of
signal detection. We show that using quantum error-correction codes a small
signal can be measured with Heisenberg limited uncertainty even in the presence
of noise. We analyze the limitations to the measurement of signals of interest
and discuss two simple examples. The possibility of long coherence times,
combined with their Heisenberg limited sensitivity to certain signals, pose
quantum error-correction codes as a promising detection scheme.

Quantum Physics