Search

By injecting two external optical beams into a broad-area laser diode, four-wave mixing is generated via gain nonlinearities in the device. The nonlinear signals are observed by spectrally analyzing the transverse far-field profile of the emission from the device. By varying the injection angle and oscillation wavelength of one of the injected beams, the spatial and frequency dependence of this nonlinear process is measured. The results support a spatially dependent dynamic carrier concentration model which includes the effects of carrier diffusion. These measurements provide a direct determination of the ambipolar diffusion constant in the device D=9.5 cm2/s. [ABSTRACT FROM AUTHOR]

Four-wave mixing is investigated in broad-area diode lasers. Two external fields are injected into the device using a phase conjugation geometry and the nonlinear four-wave mixing signal observed by performing spectrally resolved measurement of the far field. By varying the injection geometry, the excited mode of the broad-area diode can be controlled. The gain nonlinearity generates a conjugate wave within the device, thereby resulting in far-field emission in the conjugate direction. Nonlinear conjugate signal efficiency levels of ∼-21 dB have been observed. [ABSTRACT FROM AUTHOR]