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Surface plasmon polariton is a mode of electromagnetic surface wave that exists on two dielectric cross-sections (usually metal and insulator) with opposite sign of dielectric constant, which can break the diffraction limit. In an appropriate optical waveguide structure composed of metal and dielectric, light can be trapped at the subwavelength scale. Here, we propose an approach that integrates dielectric waveguiding with plasmonicsby finite-element simulation. The hybrid optical waveguide consists of an active ZnO nanowire separated from a metal surface by a nanoscale dielectric gap (10 nm). The coupling between surface plasmonic and waveguide modes allows energy to be stored and propagated in subwavelength dielectric gap. The leaky modes of ZnO nanowire lose part of their energy to the continuum of dielectric layer during propagation. Due to gain guiding, the hybrid electric leaky mode makes it possible to observe leaky-mode lasing. This approach could lead to the true integration of subwavelength lasers based on nanoscale semiconductor-based plasmons and photonics.

Zinc sulfide (ZnS) crystal is one of the important materials used to make the wide-spectrum infrared window. The ultrafast laser technology for manufacturing the nanopores with high aspect ratio provides an important approach to fabricate the photonic devices such as mid-infrared waveguide Fourier transform spectrometer etc. In this paper, a 40-times-demagnification ultrafast laser direct-writing system was built with a 4f system and a Gaussian-Bessel beam generated by a quartz axicon and a Yb:KGW laser source that operated at a wavelength of 1030 nm, a repetition rate of 100 kHz and a pulse width tunable from 223 fs to 20 ps. When the pulse energy was changed from 36 μJ to 62 μJ and the pulse duration was changed from 12.5 ps to 20 ps, the nanopore structure with a diameter of 80~320 nm was successfully written on the ZnS crystal. The surface morphology, diameter and depth of the nanopores were determined by FIB (Focused Ion Beams) ablation and SEM (Scanning Electron Microscopy) imaging. The influence of laser pulse energy and pulse width on the nanopores was studied. The results show that when the pulse width is 20 ps and the pulse energy is 48 µJ, the depth of a nanopore is about 270 µm.

Hybrid graphene/semiconductor phototransistors have attracted great attention because of their ultrahigh responsivity. However, the specific detectivity (D*) for such hybrid phototransistors obtained from source-drain electrodes is assumed to be 1/f noise. In this paper, D* of ~1.82×1011 Jones was achieved from source-gate electrodes. Compared with the same device which was measured from source-drain electrodes, D* was improved by ~500 times. This could be attributed to the carrier trapping and detrapping processes having been screened by the Schottky barrier at the interface. The rise and decay times were 4 ms and 37 ms, respectively. The temporal response speed also correspondingly improved by ~2 orders of magnitude. This work provides an alternative route toward light photodetectors with high specific detectivity and speed.

Terahertz technology is indispensable in plenty of fields due to the abundant interactions between terahertz waves and matter. In order to meet the needs of terahertz applications, the development of highly sensitive and portable terahertz detectors based on distinctive physical mechanisms and various materials with excellent properties are urgently required. Black arsenic-phosphorus is a novel two-dimensional material that has a tunable band gap and transport characteristics with varying chemical composition, which has gained widespread interest in optoelectronic applications. Recent research on b-AsxP1-x mainly focuses on infrared detection, while the detection of terahertz has not yet been applied. Herein, an antenna-coupled terahertz detector based on exfoliated multilayer black arsenic-phosphorus is demonstrated. The terahertz response performance of the detector reflects two different mechanisms, which have a competitive relationship in the detection process. In particular, the detection mechanism can be tailored by varying the chemical composition of black arsenic-phosphorus. By balancing the band gap and carrier mobility, a responsivity of over 28.23 V/W and a noise equivalent power of less than 0.53 nW/Hz1/2 are obtained at 0.37 THz. This implies that black arsenic-phosphorus has great potential in terahertz technology.

One-dimensional (1D) semiconductor nanowires have shown outstanding performance in nano-electronics and nano-photonics. However, the electrical properties of the nanowire transistors are very sensitive to interactions between the nanowires and substrates. Optimizing the device structure can improve the electrical and photodetection performance of nanowire transistors. We report a suspended In2O3 nanowire transistor fabricated by one-step lithography, showing a high mobility of 54.6 cm2V−1s−1 and a low subthreshold swing of 241.5 mVdec−1. As an ultraviolet photodetector, the phototransistor shows an extremely low dark current (~10−13 A) and a high responsivity of 1.6×105 A•W−1. This simple and effective method of suspending the channel material of a transistor can be widely used in manufacturing high-performance micro-nano devices.

Acoustic-to-seismic coupling landmine detection technology based on the unique mechanical characteristics of landmines and the acoustic-to-seismic coupling principle has broad application prospects in safe and effective detection of landmines. However, a significant amount of work must be done to study the practical landmine detection system. Among them, the acoustic coupled surface vibration signals are very weak and complicated, which has always been a challenging problem to detect such signals accurately and quickly. In this paper, the non-contact laser measurement techniques of surface vibrations based on the principle of the acoustic-to-seismic coupling landmine detection technology were reviewed, including laser Doppler interferometry, electronic speckle pattern interferometry and laser self-mixing interferometry, etc., and the application feasibility of electronic speckle-shearing pattern interferometry in acoustic-to-seismic coupling landmine detection was explored.