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arXiv · 1905.09115

Beam steering with a nonlinear optical phased array antenna

Abstract

Transition metal dichalcogenides (TMDCs) exhibit high second harmonic (SH) generation in the visible due to their non-centrosymmetric crystal structure in odd-layered form and direct bandgap transition when thinned down to a monolayer. In order to emit the SH radiation into a desired direction one requires a means to control the phase of the in-plane nonlinear polarization. Here, we couple the SH response of a monolayer MoS$_{\text{2}}$ to an optical phased array antenna and demonstrate controllable steering of the nonlinear emission. By exploiting the intrinsic SH generation by the phased array antenna we achieve uniform emission efficiency into a broad angular range. Our work has relevance for novel optoelectronic applications, such as programmable optical interconnects and on-chip LIDAR.

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Sebastian Busschaert, Nikolaus Flöry, Sotirios Papadopoulos, Markus Parzefall, Sebastian Heeg, Lukas Novotny. 2019-05-22. Beam steering with a nonlinear optical phased array antenna. https://doi.org/10.1021/acs.nanolett.9b02029

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