High-yield external optical feedback resistant partially corrugatedwaveguide laser diodes

摘要

This paper clarifies high yield external optical feedbacknresistant characteristics in partially corrugated waveguide laser diodesn(PC-LD's), compared to conventional distributed feedback laser diodesn(DFB-LD's). Based on a novel large single dynamic analysis by combiningnthe transient mirror loss (total net threshold gain) fluctuation withnthe van der Pol equations in single-mode LD's, the feedback effect ofnmirror loss on the external optical feedback resistance in single-modenLD's was found for the first time. Theoretical analysis predicted thatnin the PC-LD's, relatively stable transient mirror loss suppresses thenpositive feedback effect of mirror loss, as well as the optical outputnfluctuations under the external optical feedback. Experimental resultsnshow that the increase of the relative intensity noise in 70% PC-LD'sncould be suppressed to lower than -120 dB/Hz and the minimum RIN was asnlow as -126 dB/Hz with the external optical feedback of -20 dB