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Plasmon mediated spectrally selective and sensitivity-enhanced uncooled near-infrared detector

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Abstract

Here, we present a high performance uncooled near-infrared (NIR) detector comprising of a giga hertz (GHz) solidly mounted resonator (SMR) and gold nanorods (GNRs) arrays. By coupling the localized surface plasmon resonances of GNRs, the resonator system exhibits optimized optical response to vis-NIR region. Both simulation and experiments demonstrate the hybrid GNRs-SMR exhibit significantly enhanced optical responsive sensitivity of NIR, the tunable aspect ratios (AR) of GNRs enable resonator respond sensitively to selected light. Specially, taking advantage of the acoustofluidic effect of SMR, the GNRs can be controllably and precisely modified on the microchip surface in an ultra-short time, which addresses one of the most fundamental challenges in the localized functionalization of micro/nano scale surface. The presented work opens new directions in development of novel miniaturized, tunable NIR detector.

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  • Muralt