EXPERIMANTAL AND THEORETICAL INVESTIGATION OF FABRICATED LONG WAVELENGTH TAPERED SEMICONDUCTOR LASERS

In this study, fabrication and light output-current and longitudinal optical spectral characteristics of semiconductor lasers operating in the wavelengths of 1300 nm and 1550 nm are investigated. in addition, modelling of p-i and longitudinal optical spectrum characteristics of the lasers is obtained using rate equations. we observed that experimental results are well agreed with simulation. threshold current is measured to be 30 ma while it is 27 ma in simulation for the lasers with 1300 nm and 1550 nm wavelengths. it is also found that the threshold current increases with increasing cavity length due to an increase in the losses. furthermore, central wavelength of the optical spectra is obtained to be close to the design parameters. finally, 3-db spectral width is obtained experimentally and theoretically. 3-db spectral width difference between experiment and simulation in 1550 nm lasers is obtained to be 1.6 nm while it is 10 nm in 1300 nm lasers. because this difference obtained for 1550 nm lasers is much lower than that of 1330 nm lasers, it can be concluded that 1550 nm lasers have got better spectral stability than that of 1300 nm lasers.