Superradiance as a source of collective decoherence in quantum computers

  title={Superradiance as a source of collective decoherence in quantum computers},
  author={Deniz D. Yavuz},
  journal={Journal of The Optical Society of America B-optical Physics},
  • D. Yavuz
  • Published 1 July 2014
  • Physics
  • Journal of The Optical Society of America B-optical Physics
We analyze the radiative coupling of qubits to a common radiation bath in free space and discuss that superradiance (collective emission) results in decoherence that scales with the square of the number of qubits. This decoherence mechanism is nonlocal; the collective emission simultaneously decoheres all the qubits in the computer. Because the noise source is not local, the introduced errors are outside the applicability of the threshold theorem. As a result, we argue that the errors due to… 

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