For a long time , the electromagnetic behaviour of quantum well infrared photodetectors (QWIPs and QCDs) was insufficiently studied, and research on these systems has been hitherto rather oriented on the optimization of transport in the active layer. A formalism suitable to near field modeling of these gratings has been developed only quite recently. The study of the coupling gratings on such structures can now take advantage of the recent developments on plasmonics and metamaterials. The aim of this work is to go beyond the simplistic coupling feature of the grating and design optical structures fulfilling extra roles. To give an example, we demonstrate the possibility of discriminating the polarization of black body emission using a unidimensional grating. Based on the dispersion properties of metal/dielectric corrugated interfaces which exhibit a photonic bandgap, we concentrated all the incident electric field on a distance less than a quarter of wavelength. On an implanted pixel, such an optical structure can be used to increase the signal to noise ratio. We propose three technical solutions for an upper contact fulfilling the double function of electric contact and optical grating. We also focus on the influence of the well impurities on the photocurrent. We wish that this work will lead both to a better optimization of electromagnetic coupling and to implement new pixel integrated optical functionalities.
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