Electromagnetically induced transparency (EIT) metamaterials (MTMs) based on the bright-dark mode theory have gained great interest in slow light, sensing, and energy storage in recent years. Typically, various split ring resonators with magnetic response have been proposed as dark resonators in EIT MTMs. Here, we have employed a cut-wire (CW) and two electric-field-coupled inductor-capacitor (ELC) resonators with a pure electrical response on a liquid crystal polymer (LCP) substrate with a low loss tangent to fulfill the EIT effect in the terahertz (THz) region. The former works as the bright mode, and the latter functions as the dark mode. The EIT phenomenon results from the destructive interference between these two modes, which can be verified by numerical simulation and near field distribution. In addition, a Lorentz oscillator model was studied to quantitatively analyze the relationship between the coupling strength and the coupling distance. As a demonstration, an EIT MTM device with 5000 units was fabricated and characterized, which showed a transmission window with a peak value of 0.75 at 0.414 THz. This work may inspire new multifunctional EIT MTMs, especially the flexible applications at THz frequencies.

Heterogeneous surface with superhydrophilic/ superhydrophobic stripes (HS-s/sS) has great practical significance, which can be used in fuel cell water management, condensation heat transfer enhancement, underwater drag reduction. Herein, a fast and simple method for uniform HS-s/ sS on several mesh materials, including copper, stainless steel, and nickel, is achieved by using picosecond (ps) laser line-by-line scanning. Note that the scanning period between the lines is kept constant during processing, the HS-s/sS is formed by selforganized, while the similar structure cannot be processed on solid metal surfaces using the same parameters. The processing parameters, including scanning speed, defocus amount (DA), scanning period, and single pulse energy are systematically investigated to optimize HS-s/sS fabrication. It is found that the period of processed stripe on the mesh material is ∼1 mm, which is much larger than the scanning period. Interestingly, the as-prepared mesh surface show superhydrophobicity in the convex striped surface and superhydrophilicity in concave striped parts. The scanning electron microscopy results show that the structures on convex stripe are mainly composed of disordered hill-like structures, while the structures on the concave stripe mainly consist of periodic nanostripe structures. Moreover, the proportion of oxygen on the convex stripe is obviously higher than that on the concave stripe. The underlying mechanism of the HS-s/sS formation can be attributed to the interference between surface phonon polaritons (SPP) and the incident picosecond laser, as well as surface shock wave caused by the picosecond laser. We believe that such functional surfaces will be promising candidates for controlling liquid motion and fluid diversion processes.

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