Photon statistics of amplified spontaneous emission noise in a 10-Gbit/s optically preamplified direct-detection receiver.

We verify experimentally, over a dynamic range of 55 dB in the probability distribution, that the amplified spontaneous emission noise of the 0's from an optically preamplified receiver is degenerate Bose-Einstein distributed. Using the noise parameters extracted from the experiment, we are able to predict the sensitivity of a 10-Gbit/s direct-detection receiver.