Abstract

Recently, considerable attention has been paid to the effect of optical feedback from a phase-conjugate mirror into a single-mode semiconductor laser.^1,2 Such a feedback (PCF) eliminates the external round-trip phase change. Therefore, the intensity-noise behavior of a laser diode with PCF is quite different from that with the conventional mirror feedback. Low levels of PCF decrease the intensity noise in the laser output power.² In this work the turn-on delay jitter of laser diodes subjected to weak PCF in short external cavities is studied. We develop a theory, validated with numerical simulations, to obtain the turn-on time distrtibution. Unlike the case with a conventional mirror,³ the results are not sensitive to small variations in the position of the external miror on the optical wavelength scales. This is clearly due to the lack of external roundtrip phase change. However, the effective laser threshold is dependent upon the phase that changes due to the chirping. Therefore the turn-on time distribution becomes sensitive to the value of the linewidth enhancement factor α.

© 1994 IEEE