CONTROL OF EXTERNAL-CAVITY SEMICONDUCTOR-LASER DYNAMICS USING ELECTRICAL SELF-HETERODYNE FEEDBACK

An analysis is undertaken of a technique of additional self-heterodyne electrical feedback which is proposed for the control of optical-feed back-induced instabilities in semiconductor lasers. The stability anal ysis has been undertaken from an appropriate characteristic equation w hich is solved exactly. The work represents the first detailed analysi s of several pertinent features including the influence of two delay t ime scales on the steady states, instability conditions and spontaneou s-emission noise characteristics. Examination of the influence of addi tional electrical feedback reveals the conditions under which such fee dback effects the suppression of instabilities. The advantages of self -heterodyne-type feedback in providing additional linewidth narrowing simultaneously with stabilization of the steady-state regime is also r evealed.