The Experts below are selected from a list of 39207 Experts worldwide ranked by ideXlab platform
G Shirane - One of the best experts on this subject based on the ideXlab platform.
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neutron scattering study of spin density wave order in the superconducting state of Excess Oxygen doped la 2 cuo 4 y
Physical Review B, 1999Co-Authors: Y S Lee, R J Birgeneau, M A Kastner, Y Endoh, S Wakimoto, K Yamada, R W Erwin, S H Lee, G ShiraneAbstract:We report neutron-scattering measurements of spin-density wave order within the superconducting state of a single crystal of predominately stage-4 ${\mathrm{La}}_{2}{\mathrm{CuO}}_{4+y}$ with a ${T}_{c}$ (onset) of 42 K. The low-temperature elastic magnetic scattering is incommensurate with the lattice and is characterized by long-range order in the copper-oxide plane with the spin direction identical to that in the insulator. Between neighboring planes, the spins exhibit short-range correlations with a stacking arrangement reminiscent of that in the undoped antiferromagnetic insulator. The elastic magnetic peak intensity appears at the same temperature within the errors as the superconductivity, suggesting that the two phenomena are strongly correlated. These observations directly reveal the persistent influence of the antiferromagnetic order as the doping level increases from the insulator to the superconductor. In addition, our results confirm that spin-density wave order for incommensurabilities near $1/8$ is a robust feature of the ${\mathrm{La}}_{2}{\mathrm{CuO}}_{4}$-based superconductors.
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neutron scattering study of spin density wave order in the superconducting state of Excess Oxygen doped la sub 2 cuo sub 4 y
Physical Review B, 1999Co-Authors: R J Birgeneau, M A Kastner, Y Endoh, S Wakimoto, K Yamada, R W Erwin, G ShiraneAbstract:We report neutron-scattering measurements of spin-density wave order within the superconducting state of a single crystal of predominately stage-4 La{sub 2}CuO{sub 4+y} with a T{sub c} (onset) of 42 K. The low-temperature elastic magnetic scattering is incommensurate with the lattice and is characterized by long-range order in the copper-oxide plane with the spin direction identical to that in the insulator. Between neighboring planes, the spins exhibit short-range correlations with a stacking arrangement reminiscent of that in the undoped antiferromagnetic insulator. The elastic magnetic peak intensity appears at the same temperature within the errors as the superconductivity, suggesting that the two phenomena are strongly correlated. These observations directly reveal the persistent influence of the antiferromagnetic order as the doping level increases from the insulator to the superconductor. In addition, our results confirm that spin-density wave order for incommensurabilities near 1/8 is a robust feature of the La{sub 2}CuO{sub 4}-based superconductors. {copyright} {ital 1999} {ital The American Physical Society}
Qinggang Lu - One of the best experts on this subject based on the ideXlab platform.
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the experimental study on nitrogen oxides and so2 emission for oxy fuel circulation fluidized bed combustion with high Oxygen concentration
Fuel, 2015Co-Authors: Shiyuan Li, Mingxin Xu, Haoyu Li, Xin Wang, Qinggang LuAbstract:Oxy-fuel circulating fluidized bed combustion (CFBC) has an advantage of being operated with high Oxygen concentration, making it a better choice for CO2 capture. In order to study the emission of nitrogen oxides and SO2 under O2/RFG (recycle flue gas) firing mode with an overall O2 concentration of 50%, oxy-fuel combustion experiments with Datong coal were carried out in a 0.1 MWth oxy-fuel CFBC apparatus. The effects of different operating conditions on gaseous pollution emission, including gas staging combustion, Oxygen staging combustion, and Excess Oxygen ratio were investigated. The exper- imental results show that a lower secondary flow ratio improves the sulfur capture efficiency, although the fuel N conversion increases slightly. Oxygen staging combustion, which means decreasing the Oxygen concentration in the primary flow and increasing it in the secondary flow, is a new and safe method for oxy-fuel combustion with high Oxygen concentration. A reasonably low Excess Oxygen ratio for the oxy-fuel CFBC operation is beneficial to simultaneously enable a decrease in the fuel N conversion and an improvement in the sulfur capture efficiency.
Wojciech Nowak - One of the best experts on this subject based on the ideXlab platform.
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oxy fuel circulating fluidized bed combustion in a small pilot scale test rig
Fuel Processing Technology, 2010Co-Authors: T Czakie, Karol Sztekle, S Karski, Daniel Markiewicz, Wojciech NowakAbstract:Abstract Coal combustion under the elevated partial pressure of Oxygen in a circulating fluidized bed environment was investigated. The fuel used was bituminous coal. The concentration of Oxygen in the air was increased to 35% per volume. Excess Oxygen ranged from 1.1 to 1.3 and the temperature ranged from ca. 1073 K to 1273 K. A 0.1 MW th CFB combustor was adapted for oxy-combustion. The conversion ratios respectively studied were: carbon, sulfur and nitrogen to CO, SO 2 and NO X . An increase of nitrogen and sulfur conversion ratios and a strong decrease of incomplete combustion losses were found under the Oxygen-enriched conditions. Moreover, a strong increase in temperature was noticed during oxy-combustion.
Hideo Hosono - One of the best experts on this subject based on the ideXlab platform.
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high performance indium gallium tin oxide transistors with an al2o3 gate insulator deposited by atomic layer deposition at a low temperature of 150 c roles of hydrogen and Excess Oxygen in the al2o3 dielectric film
ACS Applied Materials & Interfaces, 2021Co-Authors: Cheol Hee Choi, Hideo Hosono, Taikyu Kim, Shigenori Ueda, Yu Shien Shiah, Junghwan Kim, Jae Kyeong JeongAbstract:In this work, high-performance amorphous In0.75Ga0.23Sn0.02O (a-IGTO) transistors with an atomic layer-deposited Al2O3 dielectric layer were fabricated at a maximum processing temperature of 150 °C. Hydrogen (H) and Excess Oxygen (Oi) in the Al2O3 film, which was controlled by adjusting the Oxygen radical density (PO2: flow rate of O2/[Ar+O2]) in the radio-frequency (rf) plasma during ALD growth of Al2O3, significantly affected the performance and stability of the resulting IGTO transistors. The concentrations of H and Oi in Al2O3/IGTO stacks according to PO2 were characterized by secondary ion mass spectroscopy, X-ray photoelectron spectroscopy, hard X-ray photoemission spectroscopy, and thermal desorption spectroscopy. The high concentration of H at a low PO2 of 2.5% caused heavy electron doping in the underlying IGTO during thermal annealing at 150 °C, leading to a conductive behavior in the resulting transistor without modulation capability. In contrast, a high PO2 condition of 20% introduced O2 molecules (or Oi) into the Al2O3 film, which negatively impacted the carrier mobility and caused anomalous photo-bias instability in the IGTO transistor. Through in-depth understanding of how to manipulate H and Oi in Al2O3 by controlling the PO2, we fabricated high-performance IGTO transistors with a high field-effect mobility (μFE) of 58.8 cm2/Vs, subthreshold gate swing (SS) of 0.12 V/decade, threshold voltage (VTH) of 0.5 V, and ION/OFF ratio of ∼109 even at the maximum processing temperature of 150 °C. Simultaneously, the optimized devices were resistant to exposure to external positive gate bias stress (PBS) and negative bias stress (NBS) for 3600 s, where the VTH shifts for exposure to PBS and NBS for this duration were 0.1 V and -0.15 V, respectively.
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effects of Excess Oxygen on operation characteristics of amorphous in ga zn o thin film transistors
Applied Physics Letters, 2011Co-Authors: Keisuke Ide, Kenji Nomura, Toshio Kamiya, Yutomo Kikuchi, Mutsumi Kimura, Hideo HosonoAbstract:Operation characteristics of amorphous In-Ga-Zn-O (a-IGZO) thin-film transistors (TFTs) were improved to a subthreshold voltage swing (S) of 217 mV (decade)−1, a mobility of ∼11.4 cm2 (Vs)−1, and a threshold voltage (Vth) of 0.1 V by O3 annealing at a temperature as low as 150 °C. However, the O3 annealing at 300 °C caused serious deterioration and exhibited a bistable transition between a large S state and a large Vth state. This transition is attributed to incorporation of Excess Oxygen and associated subgap defects with a negative-U characteristic. It also explains why a-IGZO channels deposited at high Oxygen pressures do not produce operating TFTs.
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sputtering formation of p type sno thin film transistors on glass toward oxide complimentary circuits
Applied Physics Letters, 2010Co-Authors: Hisato Yabuta, Nobuyuki Kaji, Ryo Hayashi, Hideya Kumomi, Kenji Nomura, Toshio Kamiya, Masahiro Hirano, Hideo HosonoAbstract:Thin film transistors (TFTs) using polycrystalline tin oxides (SnO–SnO2) channels were formed on glass by a conventional sputtering method and subsequent annealing treatments. SnO-channel TFTs showed p-type operation with on/off current ratios of ∼102 and field-effect mobilities of 0.24 cm2 V−1 s−1. Incorporation of Excess Oxygen to SnO channel layers did not generate holes but did electrons, which in turn led to n-type operation. This result is explained by transformation to a local SnO2-like structure and finally to SnO2. We propose a simple method to fabricate complimentary circuits by simultaneous selective formation of p- and n-channel TFTs.
Lufei Jia - One of the best experts on this subject based on the ideXlab platform.
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influence of operating parameters on n2o emission in o2 co2 combustion with high Oxygen concentration in circulating fluidized bed
Applied Energy, 2016Co-Authors: Lufei JiaAbstract:Oxy-fuel circulating fluidized bed (CFB) combustion combining the advantages of oxy-fuel combustion and CFB technology is one of the most promising technologies for capturing CO2. However, the emission of N2O in oxy-fuel CFB combustion can be high enough to raise some related environmental issues. This study investigated N2O emission in O2/CO2 CFB combustion with a high Oxygen concentration based on the experimental results using a the 0.1MWth oxy-fuel CFB. This study focused on the operating parameters. It was found that increasing the combustion temperature and overall Oxygen concentration can lead to lower N2O emission, while increasing the Excess Oxygen ratio can lead to higher N2O emission levels. Both gas staging and Oxygen staging have slight adverse influences on controlling N2O owing to the higher Oxygen concentration in the secondary gas. Finally, the Excess Oxygen ratio in the primary zone was determined in order to assess the actual effects of gas and Oxygen staging on both N2O and NO emissions.
