Percolative phase separation induced by nonuniformly distributed excess oxygens

The zero-field $^{139}$La and $^{55}$Mn nuclear magnetic resonances were studied in $\rm La_{0.8}Ca_{0.2}MnO_{3+\delta}$ with different oxygen stoichiometry $\delta$. The signal intensity, peak frequency and line broadening of the $^{139}$La NMR spectrum show that excess oxygens have a tendency to concentrate and establish local ferromagnetic ordering around themselves. These connect the previously existed ferromagnetic clusters embedded in the antiferromagnetic host, resulting in percolative conduction paths. This phase separation is not a charge segregation type, but a electroneutral type. The magnetoresistance peak at the temperature where percolative paths start to form provides a direct evidence that phase separation is one source of colossal magnetoresistance effect.Comment: 4 pages, 5 figure

High-Voltage Drain-Extended FinFET With a High-k Dielectric Field Plate

Adrain-extended (De) FinFET (DeFinFET) with a high-k dielectric field plate is proposed for high-voltage (HV) system-on-chip (SoC) applications at 10-nm CMOS technology nodes. Conventional DeFinFETs without the dielectric field plate and DeFinFETs with SiO2 and HfO2 field plate are investigated by varying the length (L-EXT) and the doping concentration (N-EXT) of the fin extension and the thickness (T-FOX) of the dielectric field plate. The optimized device with the HfO2 field plate has a high breakdown voltage (V-BD) of 8.56 V, a low specific ON-state resistance (R-ON_sp) of 6.40 Omega.mu m(2), and a large figure of merit (V-BD(2)/RON_sp) of 11.46 W/mu m(2), which are greatly improved HV performance over other devices. This indicates that the HfO2 field plate can effectively address the tradeoff between V-BD and R-ON_sp. In addition, the excellent electrical characteristics such as high ON-state current (I-ON) of 3.07 x 10(-4) A/mu m, low OFF-state current (I-OFF) of 6.54 x 10(-10) A/mu m, and small subthreshold swing (SS) of 65.54 mV/decade are observed for the optimized HfO2-DeFinFET. Consequently, the proposed design with the high-k field plate can be a pathway to realize HV DeFinFETs for SoC technology.11Nsciescopu

Improvement of Rudder Cavitation Performance Using Rudder Inflow Measurements in Large Cavitation Tunnel

One of the important things in a ship’s rudder design is the incidence angle of the rudder inflow to improve rudder cavitation performance. In the present study, the rudder inflow is measured by a 3-D LDV (laser Doppler velocimetry) system in a large cavitation tunnel, where the ship model tests are performed at a rather high Reynolds number of 107~108. Through the evaluation of the transverse velocity component using water injection experiments in the test section, the reliability of the 3-D LDV measurements is confirmed. The three-dimensional velocity components of rudder inflow between the rudder and propeller are successfully measured and are compared with numerical simulation results to see good agreement. The incidence angle distribution of the rudder inflow is obtained from the 3-D velocity components and shows a large angle at the range of 0.5 < Z/Span < 0.9, where the cavitation mainly occurred. The asymmetry-type rudder proposed based on rudder inflow measurements showed outstanding improvement of cavitation performance, compared with the flat-type rudder