May 3: Degradation of Quantum Entanglement in Optical Amplifier

This Friday, Bhaskar Roy Bardhan is going to give us a talk. As usual, food and drink will be available at 11:30AM.

Degradation of Quantum Entanglement in Optical Amplifier

Abstract:

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.

Articles to be discussed:

S. Lloyd, Science 321, 5895 pp. 1463-1465 (2008).
G.S. Agarwal and S. Chaturvedi, Optics Communications 283, 839 (2010).

Time: Friday, May 3, 11:30AM
Location: Rm 201, Nicholson Hall

Foods and drinks will be provided at 11:30AM.