Ultra-broadband supercontinuum covering a spectrum from visible to mid-infrared generated by high-power and ultrashort noise-like pulses.

To facilitate a fiber-based supercontinuum generation system, single-mode fibers with different cutoff wavelengths are introduced to serve as shortpass filters to replace conventional reflective or transmissive filters. Meanwhile, an ytterbium-doped fiber amplifier is adopted to amplify the filtrated pulses, scaling their average power to the watt level up to 4.33 W. Through this approach, ultrashort high-power laser pulses of 1.56 µm and 1.06 µm wavelengths, which are commonly used in optical communications and industrial applications, can be generated by this single system. Furthermore, it is found that the noise-like pulses still maintain their temporal features, even after they undergo multiple optical processes including amplification, supercontinuum generation, and filtration. After that, the generated pulses at 1.06 µm were launched into a photonic crystal fiber to generate a supercontinuum of 1.85 W covering a spectral range from 560 nm in the visible region to 3.5 µm in the mid-infrared region. This is one of the widest records of spectrum in broadband supercontinuum generation.

Impact of Oxygen Vacancy on the Photo-Electrical Properties of In2O3-Based Thin-Film Transistor by Doping Ga.

In this study, amorphous indium gallium oxide thin-film transistors (IGO TFTs) were fabricated by co-sputtering. Three samples with different deposition powers of the In2O3 target, namely, sample A with 50 W deposition power, sample B with 60 W deposition power, and sample C with 70 W deposition power, were investigated. The device performance revealed that oxygen vacancies are strongly dependent on indium content. However, when the deposition power of the In2O3 target increased, the number of oxygen vacancies, which act as charge carriers to improve the device performance, increased. The best performance was recorded at a threshold voltage of 1.1 V, on-off current ratio of 4.5 × 106, and subthreshold swing of 3.82 V/dec in sample B. Meanwhile, the optical properties of sample B included a responsivity of 0.16 A/W and excellent ultraviolet-to-visible rejection ratio of 8 × 104. IGO TFTs may act as photodetectors according to the results obtained for optical properties.

Nonvolatile bio-memristor fabricated with egg albumen film.

This study demonstrates the fabrication and characterization of chicken egg albumen-based bio-memristors. By introducing egg albumen as an insulator to fabricate memristor devices comprising a metal/insulator/metal sandwich structure, significant bipolar resistive switching behavior can be observed. The 1/f noise characteristics of the albumen devices were measured, and results suggested that their memory behavior results from the formation and rupture of conductive filaments. Oxygen diffusion and electrochemical redox reaction of metal ions under a sufficiently large electric field are the principal physical mechanisms of the formation and rupture of conductive filaments; these mechanisms were observed by analysis of the time-of-flight secondary ion mass spectrometry (TOF-SIMS) and resistance-temperature (R-T) measurement results. The switching property of the devices remarkably improved by heat-denaturation of proteins; reliable switching endurance of over 500 cycles accompanied by an on/off current ratio (Ion/off) of higher than 10(3) were also observed. Both resistance states could be maintained for a suitably long time (>10(4) s). Taking the results together, the present study reveals for the first time that chicken egg albumen is a promising material for nonvolatile memory applications.

Negative differential resistance behavior and memory effect in laterally bridged ZnO nanorods grown by hydrothermal method.

A novel memory device based on laterally bridged ZnO nanorods (NRs) in the opposite direction was fabricated by the hydrothermal growth method and characterized. The electrodes were defined by a simple photolithography method. This method has lower cost, simpler process, and higher reliability than the traditional focused ion beam lithography method. For the first time, the negative differential resistance and bistable unipolar resistive switching (RS) behavior in the current-voltage curve was observed at room temperature. The memory device is stable and rewritable; it has an ultra-low current level of about 1 × 10(-13) A in the high resistance state; and it is nonvolatile with an on-off current ratio of up to 1.56 × 10(6). Moreover, its peak-to-valley current ratio of negative differential resistance behavior is greater than 1.76 × 10(2). The negative differential resistance and RS behavior of this device may be related to the boundaries between the opposite bridged ZnO NRs. Specifically, the RS behavior found in ZnO NR devices with a remarkable isolated boundary at the NR/NR interface was discussed for the first time. The memory mechanism of laterally bridged ZnO NR-based devices has not been discussed in the literature yet. In this work, results show that laterally bridged ZnO NR-based devices may have next-generation resistive memories and nanoelectronic applications.