Estimation of pulsed laser-induced single event transient in a partially depleted silicon-on-insulator 0.18-μm MOSFET

In this paper, we investigate the single event transient(SET) occurring in partially depleted silicon-on-insulator(PDSOI) metal–oxide–semiconductor(MOS) devices irradiated by pulsed laser beams. Transient signal characteristics of a 0.18-μm single MOS device, such as SET pulse width, pulse maximum, and collected charge, are measured and analyzed at wafer level. We analyze in detail the influences of supply voltage and pulse energy on the SET characteristics of the device under test(DUT). The dependences of SET characteristics on drain-induced barrier lowering(DIBL) and the parasitic bipolar junction transistor(PBJT) are also discussed. These results provide a guide for radiation-hardened deep sub-micrometer PDSOI technology for space electronics applications.     

A power and wavelength detuning-dependent hysteresis loop in a single mode Fabry-Prot laser diode

In this paper, we observe experimentally the optical bistability induced by the side-mode injection power and wave-length detuning in a single mode Fabry-Prot laser diode (SMFP-LD). Results show that the bistability characteristics of the dominant and injected modes are strongly dependent on the injected input optical power and wavelength detuning in an SMFP-LD. We observe three types of hysteresis loops: counterclockwise, clockwise, and butterfly hysteresis with various loop widths. In the case of a bistability loop caused by injection power, the transition from counterclockwise to clockwise in the hysteresis direction with the wavelength detuning from 0.028 nm to 0.112 nm is observed in a way of butterfly hysteresis for the dominant mode by increasing the wavelength detuning. The width of hysteresis loop, induced by wavelength detuning is also changed while the injection power is enhanced from 7 dBm to 5 dBm.     

Phase transformation and nanograting structure on TiO2 rutile single crystal induced by infrared femtosecond laser

In this paper, TitaiJum dioxide （TiO2） rutile single crystal was irradiated by infrared femtosecond laser pulses with repetition rate of 250 kHz. For a P-polarized femtosecond laser, the periodic nanograting structure on the ablation crater surface was formed . The periodicity is much less than the laser wavelength. The direction of nanograting alignment depends on the polarization laser beam. Micro-Raman spectra show that the intensity of Eg Raman vibrating mode of rutile phase increases and that of Alg Raman vibrating mode decreases apparently within the ablation crater. With the increase of irradiation time and laser average power, the Raman vibrating modes of anatase phase emerged. Rutile phase of TiO2 single crystal is partly transformed into anatase phase.[第一段]     

Field-free molecular orientation induced by combined femtosecond single- and dual-color laser pulses：The role of delay time and quantum interference

The coherent control of field-free molecular orientation of CO with combined femtosecond single- and dual-color laser pulses has been theoretically studied. The effect of the delay time between the femtosecond single- and dual-color laser pulses is discussed, and the physical mechanism of the enhancement of molecular orientation with pre-alignment of the molecule is investigated. It is found that the basic mechanism is based on the creation of a rotational wave packet by the femtosecond single-color laser pulse. Furthermore, we investigate the interference between multiple rotational excitation pathways following pre-alignment with femtosecond single-color laser pulse. It is shown that such interference can lead to an enhancement of the orientation of CO molecule by a factor of 1.6.     

A comparative study of YBa2Cu3O7-δ/YSZ bilayer films deposited on silicon-on-insulator substrates with and without HF pretreatment

Highly epitaxial YBa2Cu3O7-δ (YBCO) and yttria-stabilized zirconia (YSZ) bilayer thin films have been deposited on silicon-on-insulator (SOI) substrates by using in situ pulsed laser deposition (PLD) technique. In the experiment, the native amorphous SiO2 layers on some of the SOI substrates are removed by dipping them in a 10% HF solution for 15 s. Comparing several qualities of films grown on substrates with or without HF pretreatment, such as thin film crystallinity, general surface roughness, temperature dependence of resistance, surface morphology, as well as average crack spacing and crack width, naturally leads to the conclusion that preserving the native SiO2 layer on the surface of the SOI substrate can not only simplify the experimental process but can also achieve fairly high quality YSZ and YBCO thin films.     

Metal–insulator transition induced by non-stoichiometry of surface layer and molecular reactions on single crystal KTaO3

In the study we present results on topography, morphology, chemical composition, electronic structure and electrical properties of the (100) surface layer of KTaO₃ single crystal caused by sputtering with Ar⁺ ion beam with energy of 1 keV. Several surface sensitive techniques, i.e. X-ray photoelectron spectroscopy (XPS), local conductivity of atomic force microscopy (LC-AFM), and Kelvin Probe Force Microscopy (KPFM) were used. The observed changes in the electronic structure were explained as a result of the chemical decomposition of the surface layer. A correlation between the electronic states which appeared in the energy gap and the changes in charge state of Ta ions was found. The activation energy related to averaged local conductivity temperature dependence was estimated from Arrhenius plot. It was also found, that variations in the local contact potential difference (LCPD) indicated changes in the chemical composition in nano-scale. The chemical reconstruction of the KTaO₃ surface modified by Ar⁺ ion beam was deduced. This non-homogeneity corresponded to 2-D non-homogeneity of the local electric conduction (LC-AFM), which occurred within nano-areas after sputtering. Chemical reactivity of the modified surface with CO₂ and O₂ was observed. The reversibility of the Ar⁺ induced loss of oxygen non-stoichiometry was observed after the sample was exposed to various doses of O₂. The successful reversibility occurred after oxidation process at high temperature, i.e. 300 °C.     

Generation and characterization of millimeter-scale plasmas for the research of laser plasma interactions on Shenguang-Ⅲ prototype

In order to produce millimeter-scale plasmas for the research of laser-plasma interactions(LPIs),gasbag target is designed and tested on Shenguang-Ⅲ prototype laser facility.The x-ray pinhole images show that millimeter-scale plasmas are produced with the gasbag.The electron temperature inferred from the stimulated Raman scattering(SRS) spectrum is about 1.6 keV.The SRS spectrum also indicates that the electron density has a flat region within the duration of 200 ps.The obvious differences between the results of the gasbag and that of the void half hohlraum show the feasibility of the gasbag target in creating millimeter-scale plasmas.The LPIs in these millimeter-scale plasmas may partially mimic those in the ignition condition because the duration of the existence of a flat plasma density is much larger than the growth time of the two main instabilities,i.e.,SRS and stimulated Brillouin scattering(SBS).So we make the conclusion that the gasbag target can be used to research the large-scale LPIs.     

Comment on “Symmetry properties of three-dimensional magnetization distributions induced by focused circularly polarized lights”

It is pointed out that the paper entitled ‘Symmetry properties of three-dimensional magnetization distributions induced by focused circularly polarized lights’ (Optik 121, 2062 (2010)) presents an incorrect statement and a misleading figure.     

Effects of temperature and input energy on a quasi-three-level emission cross section of Nd3＋：yAG pumped by a flashlamp

The influence of temperature and input energy on the fluorescence emission cross section of Nd 3+ :YAG crystal is studied. The stimulated emission cross sections of quasi-three-level systems are determined in a temperature range from 30 to 60℃ and an input energy range from 18 to 75 J. The cross section is found to be decreased when the temperature and the input energy are increased. This is attributed to the thermal broadening mechanism of the emission line. This study is relevant for the development of laser design.     

Size reduction of “reformed casein micelles” by high-power ultrasound and high hydrostatic pressure

We investigated the effect of ultrasound (US) and high hydrostatic pressure (HHP) on the size of reformed casein micelles (RMCs) obtained by titrating calcium and phosphorous solution into sodium caseinate solutions. Both US and HHP reduced the size of the RMCs. A decrease in size from ~200 nm to ~170 nm when US (20 kHz, 0.46 W/mL) was applied for 30 min; and down to ~85 nm when HHP was applied 500 MPa for 15 min. Electron microscopic analysis showed that the RMCs before and after US are similar to milk native casein micelles, and that HHP extensively disintegrated the RMCs. Small angle X-ray scattering and SDS-PAGE showed that the internal structure of the RMCs as well as the casein molecules are not affected by the US and HHP treatments.     

Erratum to “Simultaneous effects of magnetic field and space porosity on compressible Maxwell fluid transport induced by a surface acoustic wave in a microchannel”

We would like to acknowledge the misprinted terms in our published paper “Simultaneous effects of magnetic field and space porosity on compressible Maxwell fluid transport induced by a surface acoustic wave in a microchannel” [Chin. Phys. B 22 124702 (2013)]. Since only two misprints exist and the main results of the published paper are correct, we present the correct equations in this erratum.