Sub-Tb/s Physical Random Bit Generators Based on Direct Detection of Amplified Spontaneous Emission Signals

The most common optical amplified spontaneous emission sources can become the ultimate tools for the generation of ultra-broadband truly random bit sequences (TRBS). By using a straightforward configuration we experimentally prove that the amplified spontaneous emission noise of an optical amplifier-either an Er
⁺³
-doped fiber amplifier (EDFA) or an InGaAs semiconductor optical amplifier (SOA)-is an efficient source for TRBS generation. A bit rate up to 560 Gb/s has been recorded, seeded by the direct detection of the unfiltered spontaneous-spontaneous (sp-sp) optical intensity beat noise on a broadband photoreceiver. The generation rate is practically limited only by the detection bandwidth, the electronic digitization process and the post-processing circuitry. The proposed mechanism passes the existing benchmarks of randomness.