Publications by authors named "Qunfeng Shao"

In this work, the phenomenon of the voltage generation is explored by using the molecular dynamics simulations, which is performed by driving a nano-sized droplet of room temperature ionic liquids moving along the monolayer graphene sheet for the first time. The studies show that the cations and anions of the droplet will move with velocity nonlinearly increasing to saturation arising by the force balance. The traditional equation for calculating the induced voltage is developed by taking the charge density into consideration, and larger induced voltages in μV-scale are obtained from the nano-size simulation systems based on the ionic liquids (ILs) for its enhanced ionic drifting velocities.

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An optofluidic waveguide with a simple two-terminal electrode geometry, when filled with an ionic liquid (IL), forms a lateral electric double-layer capacitor under a direct current (DC) electric field, which allows the realization of an extremely high carrier density in the vicinity of the electrode surface and terminals to modulate optical transmission at room temperature under low voltage operation (0 to 4 V). The unique electro-optical phenomenon of ILs was investigated at three wavelengths (663, 1330 and 1530 nm) using two waveguide geometries. Strong electro-optical modulations with different efficiencies were observed at the two near-infrared (NIR) wavelengths, while no detectable modulation was observed at 663 nm.

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We propose a multilayered superlens comprising alternately layered metal and dielectric films with layers of nonequal thickness to realize subwavelength imaging, even when permittivities of the metal and dielectric are mismatched. Based on ideal imaging conditions, the exact constraint relations about the thickness of each dielectric layer and the permittivity of the surrounding medium of the multilayered superlens are first acquired when the superlens is modeled by the effective medium theory. Theoretical analysis and numerical simulations indicate that a multilayered superlens with constraint relations can realize subwavelength imaging at wavelengths of 335 to 385 nm.

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