How much quantum noise of amplifiers is detrimental to entanglement Academic Article uri icon


  • We analyze the effect of the quantum noise of an amplifier on the entanglement properties of an input state. We consider both phase insensitive and phase sensitive amplification and specialize to Gaussian states for which entanglement measures are well developed. In the case of phase insensitive amplification in which both the modes are symmetrically amplified, we find that the entanglement in the output state vanishes if the intensity gain exceeds a limiting value 2 / (1 + exp [- EN]) where EN is the logarithmic negativity of the input state which quantifies the initial entanglement between the two modes. The entanglement between the two modes at the output is found to be more robust if only one mode is amplified. 2009 Elsevier B.V. All rights reserved.

published proceedings

  • Optics Communications

author list (cited authors)

  • Agarwal, G. S., & Chaturvedi, S.

citation count

  • 15

complete list of authors

  • Agarwal, GS||Chaturvedi, S

publication date

  • March 2010