Ultimate output parameters of laser-diode bars and arrays

An analysis was made of the influence of the series resistance of the heterostructure, of the threshold current density, and of the external differential quantum efficiency on the maximum efficiency of laser linear arrays (bars). It was found that the maximum efficiency can reach 75%. A heat sink design is suggested for ensuring that the ultimate output power is limited only by catastrophic optical damage to the cavity mirrors. The estimated ultimate output power density obtainable from a two-dimensional laser-diode array is 10 kW cm^–2.