AMORPHOUS PHASE FORMATION OF Mo_(1-x)Ge_(x),Mo_(1-x)Si_(x),FILMS AND THEIR SUPERCONDUCTING PROPERTIES

Mo_(1-x)Ge_(x),Mo_(1-x)Si_(x),films were prepared by getter sputtering onto liquid nitrogen cooled substrates.The amorphous phase formations were Ge>22 at.%,Si>18 at.%respectively.With the increase of Ge,Si content,Tc decreased from 6 to 3K in the amorphous state.The measured results of(dBc2/dT)T_(c),Jc andρ(300K)/ρ(8K)indicated that the four chosen Mo_(1-x)Si_(x)films exhibit fundamental characteristics of amorphous superconductors.

Effects of growing conditions on the electric and magnetic properties of strained La_(2/3)Sr_(1/3)MnO_3 thin films

We investigate the growing condition dependences of magnetic and electric properties of the La2/3Sr1/3MnO3 thin films grown on SrTiO3（001） substrates.With reducing the film thickness and growth pressure,the Curie temperature（Tc）drops off,and the magnetism and metallicity are suppressed.At an appropriate deposition temperature,we can obtain the best texture and remarkably enhance the magnetic and electrical properties.However,the resistivity of film cannot be modulated by changing the dc current and green light intensity.This result may be induced by the coherent strains in the epitaxially grown film due to its lattice mismatching that of the SrTiO3 substrate.Furthermore,we show that the relations between the magnetism and the resistivity for the typical films with different thickness values.For the 13.4-nm-thick film,the R-T curve presents two transition behaviors：insulator-to-metal and metal-to-insulator in the cooling process：the former corresponds to magnetic transition,and the later correlates with thermal excitation conduction.

Influence of the Heat Treatment Duration on the Critical Temperature for the Break-Down of Vertical Bloch Line Chains

For longer heat treatment duration(10 and 30 min),near and within the transi-tion region,the softening fraction p has an obvious,but not very large increase and the increment for 30min is greater than that for 10min.Ag a result,the criticad temperature To is only lowered by 2-3℃ for a typical saouple.The above results indicate the existence of a quasi-gtatic athermal instability,and the thermal activation of Bloch points is only of secondany importance.

Development of the Atomic Force Microscopy Research Technique for the Nanostructures on the Vertical Edge of Thin Insulating Film

In this work, a development of a method of a thin insulating film vertical edge visualization of metal-insulator-metal （MIM） memory cells with atomic force microscopy （AFM） using a modified Omicron UHV AFM/STM microscope was performed. This included a development of a technique of the AFM visualization of segments of a vertical edge of thin insulator SiO2 film structures on a conductive substrate, a comparison of AFM topography and current profilograms for the edge profiles, and an Omicron microscope custom upgrade. The latter allowed us to perform the AFM probe positioning to any specific area of the sample in the scanning plane by two coordinates with an order of precision of 1 micrometer. The method is illustrated with the experimental results of AFM investigations of the special MIM structures with comb-type topology, and of the cells of functioning memory matrices with 20 nm thin silicon dioxide film open edge perimeter and TiN lower electrode, including topography/current profilograms. As a conclusion, our ongoing work on the AFM visualization of a complete perimeter of a SiO2 open edge of memory cells with a special new topology with a goal to visualize conductive phase nanoparticles during switching processes is briefly overviewed.

Observation of Self-Frequency Doubling in Diode-Pumped Mode-Locked Nd-Doped La3Ga5SiO14 Laser

A diode-pumped passively mode-locked Nd-doped La3Ga5SiO14 （Nd：LGS） laser is realized by using a semicon- ductor saturable absorber mirror. With the pump power of 2 W, we obtain a 532nm self-frequency doubling （SFD） laser together with a lO.9ps fundamental laser at the repetition rate of 173.7MHz. To the best of our knowledge, it is the first time for self-frequency doubling in the diode-pumped mode-locked Nd：LGS laser. Benefited from the diode lasers and its self-frequency doubling property, Nd：LGS could be a potential candidate for compact, stable and cheap ultrafast green laser sources.

Plasma Treatment of Industrial Landfill Leachate by Atmospheric Pressure Dielectric Barrier Discharges

An dielectric barrier discharge （DBD） system in atmospheric pressure utilized for the treatment of industrial landfill leachate is reported. The discharge parameters, such as the operating frequency, gas flow rate, and treating duration, were found to affect significantly the removal of ammonia nitrogen （AN） in industrial landfill leachate. An increase in treating duration leads to an obvious increase in the removal efficiency of AN （up to 83%） and the leachate color changed from deep grey-black to transparent. Thus the dielectric barrier discharges in atmospheric pressure could degrade the landfill leachate effectively. Typical waveforms of both applied voltage and discharge current were also presented for analyzing the discharge processes under different discharge parameters. Optical emission spectra measurements indicate that oxidation species generated in oxygen DBD plasma play a crucial role in removing AN, oxidizing organic and inorganic substances and decolorizing the landfill leachate.

MULTIPHOTON IONIZATION SPECTRUM OF TOLUENE

We have obtained the highly excited state spectrum of toluene using ultraviolet two-photon resonance three-photon ionization.We assign the observed structure to three new Rydberg series converging to the first ionization potential.

Fabrication and electrical properties of a carbon nanotube quantum dot

Single-walled carbon nanotubes （SWNTs） were synthesized by pyrolyzing methane （CH4） at a temperature of 900℃ on SiO2 substrates pre-coated with iron nano-particles. Electrical contacts were fabricated onto one of the SWNTs by using an electron beam lithography process. Coulomb blockade and single-electron tunnelling characters were found at low temperatures, indicating that the SWNT in-between the electrodes forms a quantum dot. It is found that the Coulomb gap of the quantum dot is about 8.57 meV, and the factor α, which converts the gate voltage to the true electrostatic potential shift, is around 200 for this device.

SUPERCONDUCTIVITY AT 89K OF Ba-Y-Cu-O THIN FILMS

High Tc Ba-Y-Cu-O thin films have been successfully prepared by the RF magnetron sputtering method.The highest Tc onset is determined to be 89.5K and the Tc midpoint is about 55K.Inductive measurement showed that the samples are diamagnetic and the Meissner effect appeared around 10K.

Application research on large-scale battery energy storage system under Global Energy Interconnection framework

In the context of constructing Global Energy Interconnection(GEI), energy storage technology, as one of the important basic supporting technologies in power system, will play an important role in the energy configuration and optimization. Based on the most promising battery energy storage technology, this paper introduces the current status of the grid technology, the application of large-scale energy storage technology and the supporting role of battery energy storage for GEI. Based on several key technologies of large-scale battery energy storage system, preliminary analysis of the standard system construction of energy storage system is made, and the future prospect is put forward.

China’s participation in the international RRT for I_(c) measurement of superconducting cables organized by IEC/TC90

Currently,IEC/TC90 is working on standardizing the method for measuring critical current(Ic)in superconducting cables.At the end of 2020,an international round robin test(RRT)was organized,in which five Chinese institutions participated,and four accomplished the test.The electric-field versus current(E-I)curves obtained by each institution are highly repeatable.Those obtained by different institutions are nearly identical after appropriate curve averaging,indicating high reproducibility,except the last participant's inner core curves.The discrepancy was later determined to be the result of sample cable damage.After excluding highly deviated data,it is determined that the maximum relative standard uncertainty in I_(c) is 0.7%,and the maximum relative standard uncertainty in n-value is 12.8%.The I_(c)values are comparable to Japan's domestic RRT results,but the n-values are significantly different.The test results support the DC four-terminal method as a recommended test method,with a target relative uncertainty of less than 2%for the Ic value.

Intermetallic Cu_(5)Zr Clusters Anchored on Hierarchical Nanoporous Copper as Efficient Catalysts for Hydrogen Evolution Reaction

Designing highly active and robust platinum-free electrocatalysts for hydrogen evolution reaction is vital for large-scale and efficient production of hydrogen through electrochemical water splitting.Here,we report nonprecious intermetallic Cu_(5)Zr clusters that are in situ anchored on hierarchical nanoporous copper(NP Cu/Cu_(5)Zr)for efficient hydrogen evolution in alkaline medium.By virtue of hydroxygenated zirconium atoms activating their nearby Cu-Cu bridge sites with appropriate hydrogenbinding energy,the Cu_(5)Zr clusters have a high electrocatalytic activity toward the hydrogen evolution reaction.Associated with unique architecture featured with steady and bicontinuous nanoporous copper skeleton that facilitates electron transfer and electrolyte accessibility,the self-supported monolithic NP Cu/Cu_(5)Zr electrodes boost violent hydrogen gas release,realizing ultrahigh current density of 500mAcm^(-2) at a low potential of-280mV versus reversible hydrogen electrode,with exceptional stability in 1M KOH solution.The electrochemical properties outperform those of state-of-the-art nonprecious metal electrocatalysts and make them promising candidates as electrodes in water splitting devices.

Serration and Noise Behavior in Advanced Materials

The Chinese Materials Research Society（C-MRS）Conference（2015）was held in the Guizhou Park Hotel International Conference Center,Guiyang,China,from July 10-14,2015.This conference consists of 30symposia,including 4international symposia.As one of 4international symposia,＂Serration and noise behavior in advanced materials＂