Locking of diode gain modules using optical conjugation techniques

This report reviews results of a study program to investigate technical issues relating to the coupling of multiple diode lasers using a phase conjugate resonator. We present calculations showing the effects on the far-field intensity distribution of either systematic or random phase differences between adjacent gain elements; these results dramatically illustrate the beneficial impact of exact phase locking. The use of phase conjugation to phase-lock the individual emitters is suggested, and computer calculations showing the beneficial effects on the far-field intensity distribution are reviewed. The normal modes of a multiple-element diode chip are are derived; this information allows one to determine phase relationships characteristics of each mode. These relationships can be used to identify approaches that might be employed to favor one particular mode in a practical device.