Harnessing nonlinearities near material absorption resonances for reducing losses in plasmonic modulators

The electro-optic coefficient (Pockels coefficient) is largest around the absorption resonance of a material. Here, we show that the overall losses, the power consumption and the footprint of plasmonic electro-optic modulators can be reduced when a device is operated in the vicinity of absorption resonances of an electro-optical material. This near-resonant operation in plasmonics is contrary to what is known from photonics where off-resonant operation is required to minimize the overall losses. The findings are supported by experiments demonstrating a reduction in voltage-length product by a factor of 3 and a reduction in loss by a factor 2 when operating a plasmonic modulator near resonance compared to off-resonant. (C) 2017 Optical Society of America