Abstract
The effects of the external optical cavity parameters (external optical cavity length (
L
ext
), amplitude coupling (
C
o
) and anti-reflection coating (ARC) reflectivity coefficients) on the noise and modulation spectra of a fiber grating Fabry–Perot laser are numerically analyzed for designing a laser that operates in strong feedback regime (Regime V). Fiber Bragg grating (FBG) is used as a wavelength selective element to control the properties of the laser output by controlling the external optical feedback (OFB) level. The study is performed by modifying a set of rate equations that are solved by considering the effects of external OFB and ambient temperature (
T
) variations. We proposed a model to calculate the temperature dependence (TD) of laser characteristics according to the TD of laser parameters. An accurate analytical expression for the TD of threshold carrier density (
N
th,fe
) has been derived. The TD of
N
th,fe
was calculated according to the TD of laser cavity parameters instead of using well-known empirical Pankove relationship via the use of characteristics temperature (
T
o
) and current (
I
o
). Results show that the optimum external fiber length (
L
ext
) is 3.1 cm. Also, it is shown that ARC with reflectivity value of 1 × 10
−2
is sufficient for the laser to operate at low noise, good modulation response, and low fabrication complexity.