Heterodyne detection of optical terahertz beat-tones
based on semiconductor optical amplifier
Philippe, Severine, Maldonado-Basilio, Ramón, Latkowski, SylwesterORCID: 0000-0003-4464-4097 and Landais, PascalORCID: 0000-0002-4807-0695
(2011)
Heterodyne detection of optical terahertz beat-tones
based on semiconductor optical amplifier.
In: 13th International Conference on Transparent Optical Networks, 26-30 June 2011, Stockholm, Sweden.
In this paper, a detection scheme based on four wave mixing in a semiconductor optical amplifier (SOA) is used
to measure the frequency and bandwidth of the optical terahertz beat-tone signal generated by a passively mode
locked semiconductor laser. Two signals from external cavity lasers are injected into an SOA, which acts as
a local oscillator at their detuning frequency. The device under test is a passively mode locked laser with a beattone frequency in the terahertz spectrum. Its optical signal is injected in the SOA, which also acts as a frequency
mixer. The frequency and linewidth of the terahertz signal are then measured by retrieving the intermediate
frequency detected by a low bandwidth photodiode and an electrical spectrum analyser.