Subwavelength grating structures have been studied in the last two decades for a wide range of integrated optoelectronic applications that include narrow-band filters, lasers, couplers and broadband high reflectors. In particular, using high-contrast refractive indices, broadband reflectivities exceeding 99% have been demonstrated in such grating structures. In this study, we investigate an active mirror structure by embedding a gain medium. We call these devices gain-embedded meta-mirrors (GEMMs). Our optical wave propagation analysis uses a RCWA software to identify optimum GEMM structures that provide highest active reflectivity. An RCWA design procedure that can be interpreted in terms of elementary grating diffraction theory is presented. The procedure optimizes high reflectivity as well as manufacturing tolerance. A key advantage of DBR-free membrane VECSELs has been their potential for efficient heat removal. GEMM devices equally offer this advantage with the added benefit that the optical modes are only evanescent in the thermal substrate (diamond, SiC or sapphire). We will show that this property will allow us to perform more efficient heat-sinking of the thermal substrate. We will also present our preliminary experimental results on fabricating a GEMM device using e-beam lithography and AlGaAs /GaAs/AlGaAs double heterostructures as the gain medium.
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