The lasing wavelength of a semiconductor laser makes chirp when it is modulated directly due to the oscillation of injected carrier density. This wavelength chirp or the dynamic wavelength shift is normally larger than the sideband of modulation. The chirp also occurs in external modulators due to the variation of refractive index of the medium. Thus the wavelength chirp limits the transmission bandwidth of fiber transmission.

© 1989 Optical Society of America

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