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We first demonstrate a high-efficiency composite Tm-doped yttrium aluminum garnet laser end-pumped with a narrow-linewidth laser diode, which was locked at a wavelength of 784.9 nm with volume Bragg gratings. The locked pump wavelength was experimentally determined by the excitation peak, which was also the absorption peak of a 3.5 at.% Tm:YAG crystal around 785 nm, for the improvement of laser efficiency under high-intensity pumping. Under an absorbed pump power of 24.64 W, a maximum output power of 11.12 W at 2018 nm was obtained, corresponding to an optical to optical conversion efficiency of 45.1% and a slope efficiency of 52.4%.

La3Ga5SiO14 (LGS) has been designed and used successfully not only as an electro-optical (EO) Q-switch but also as the optically active crystal in an Nd:YAG (yttrium aluminum garnet) pulse-off laser cavity with two-rod birefringence compensation in this paper. A maximum average output power of 15.8 W with a pulse width of 21 ns was obtained at the maximum repetition rate of 1 kHz, and the dynamic–static ratio was 75%. Experimental results revealed that the spatial distribution of the laser intensity with the two LGS crystals inserted between two identical Nd:YAG rods was significantly better than the spatial distribution with no birefringence compensation or a KD P EO Q-switcher.

We demonstrate an all-normal-dispersion mode-locked fiber laser based on a piece of large-core Yb-doped multi-mode fiber. High order modes are suppressed by coiling the gain fiber to produce large loss for the high modes but low loss for the fundamental mode. Mode-locking is self-starting by exploiting a combination of a grating-aperture based spectral filter with a nonlinear polarization evolution effect. The laser directly delivers 1.1 ps, 107 nJ pulses at a repetition rate of 76.7 MHz, with an average power of up to 8.2 W. The pulses can be compressed externally to 210 fs with a peak power of up to 350 kW.

This work presents a facile way, i.e. phase-separation-induced self-assembly, to prepare TiO(2) nanodots on a substrate. This method induces convective flow in a spin-coated titanium tetrabutoxide (TBOT)/polyvinyl pyrrolidone (PVP)/ethanol liquid film through the Marangoni effect and turns TBOT into crystalline TiO(2) nanodots on a substrate after calcination. The size and density of the TiO(2) nanodots can be finely tailored by controlling the concentrations of TBOT and PVP in the precursor sol. The TiO(2) nanodot-deposited surface showed a hydrophilic characteristic and the wettability was obviously improved by increasing nanodot size.

We present a study of phase-separation-induced self-assembled TiO2 nanodots. The Marangoni effect is utilized in the preparation of this TiO2 nanostructure. Unique and strong ultraviolet (UV) luminescence is observed from the TiO2 nanodots at room temperature. As the nanodot size reduces from 93 to 48 nm, the bandgap energy shifts from 3.43 to 3.76 eV and the luminescence peak energy increases from 3.38 to 3.58 eV. High electron emission at low electric field is also obtained from TiO2 nanodots. The turn-on field and threshold field for emission current densities of 1 µA cm−2 and 1 mA cm−2 are as low as 0.7 and 3.7 V µm−1, the lowest values ever reported for TiO2 materials.

Position- and density-controlled ZnO nanorod arrays (ZNAs) were successfully grown on a Si substrate through a low temperature (90 °C) hydrothermal approach assisted by pre-formed ZnO micro/nanodots. The ZnO dots on Si substrates were prepared by a spin-coating technique, through which the pattern and density of the dots could be easily changed. Accordingly, the position- and density-controlled growth of ZNAs was achieved. For the resulting density-controlled ZNAs, the density could range from (5.6 ± 0.01) × 10(2) to (1.2 ± 0.01) × 10(2) rods µm(-2). The room-temperature photoluminescence (PL) spectrum of ZNAs exhibited excellent UV emission. The water wettability measurements of the ZNAs with different density showed good hydrophobicity, and the ZNAs with the lowest density revealed a superhydrophobic characteristic with a water contact angle of 166.1°.

High-density single-crystalline orthorhombic TiSi nanorods and nanopins have been successfully prepared for the first time on a Ti5Si3 layer by chemical vapor deposition, using SiH4 and TiCl4 as the precursors. The quadrate nanorods are approximately 0.5 µm long and 30 nm × 30 nm in area. The nanopins are 0.7–1 µm long in total, with the quadrate tip about 200 nm long and 50 nm × 50 nm in area. The TiSi nanorods and nanopins grow along the [110] direction of the orthorhombic TiSi crystal from the bottom, with the tip being pushed upwards. The growth process can be defined as a self-induced growth. The self-induction mechanism addressed here expands our understanding of growing nanostructures.