Open AccessOperating regimes of a controlled dual‐wavelength semiconductor laser system through four‐wave mixing‐ mediated by injection‐locking
Author(s) -
Roberts Daniel R.G.,
Pierce Iestyn
Publication year - 2019
Publication title -
iet optoelectronics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.379
H-Index - 42
eISSN - 1751-8776
pISSN - 1751-8768
DOI - 10.1049/iet-opt.2018.5019
Subject(s) - injection locking , phase locking , laser , semiconductor laser theory , diode , frequency offset , physics , mixing (physics) , frequency response , optics , wavelength , four wave mixing , harmonic , nonlinear system , nonlinear optics , optoelectronics , acoustics , computer science , quantum mechanics , telecommunications , engineering , channel (broadcasting) , electrical engineering , orthogonal frequency division multiplexing
A method of generating a non‐zero frequency spacing between two laser diodes, using four‐wave mixing, mediated by injection‐locking in order to potentially realise THz radiation is presented. Four distinct regimes of operation are observed, including a periodic response, where the oscillations are simply related to the relaxation oscillations of the system; a periodic response with multiple frequency components, where there is a harmonic relationship between the fundamental frequency and the other frequency components; a chaotic response, where the apparent frequency components are not harmonically related; and finally the locking condition between the lasers, where a continuous wave operation is apparent. A clear linear relationship between the frequency offset and the detuning frequency while operating under the locking condition is observed, and there is a clear transition in behaviour on either side of the locking region, where the system shows a nonlinear behaviour. For higher injection rates, locking is only observed at either end of the locking region, and from this arises a so‐called generalised locking region.