Low-noise optical amplifiers using polariton transition

Summary form only given. Optical amplifiers in fiber transmission systems are key devices for transmitting optical signals over a long distance. However, it is well known that the noise figure (NF) of conventional amplifiers, such as a semiconductor optical amplifier (SOA), cannot be reduced to less than 3 dB (the quantum limit) because they use induced radiation for amplification. We propose a new amplifier that uses excitonic polariton transition, and whose NF is expected to be less than 3 dB.