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Magnetic Switching Dynamics and Tunnel Magnetoresistance Effect Based on Spin-Splitting Noncollinear Antiferromagnet Mn_(3)Pt

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Chinese Physics Letters 2024年第4期41卷 132-138页

作者：朱蒙董建艇李新录郑凡星周晔吴琨张佳 School of Physics and Wuhan National High Magnetic field center Huazhong University of Science and TechnologyWuhan 430074China

In comparison to ferromagnets,antiferromagnets are believed to have superior advantages for applications in next-generation magnetic storage devices,including fast spin dynamics,vanishing stray fields and robust against external magnetic field,***,unlike ferromagnetic orders,which could be detected through tunneling magnetoresistance effect in magnetic tunnel junctions,the antiferromagnetic order(i.e.,Néel vector)cannot be effectively detected by the similar mechanism due to the spin degeneracy of conventional *** discovered spin-splitting noncollinear antiferromagnets,such as Mn_(3)Pt with momentum-dependent spin polarization due to their special magnetic space group,make it possible to achieve remarkable tunneling magnetoresistance effects in noncollinear antiferromagnetic tunnel *** first-principles calculations,we demonstrate that the tunneling magnetoresistance ratio can reach more than 800% in Mn_(3)Pt/perovskite oxides/Mn_(3)Pt antiferromagnetic tunnel *** also reveal the switching dynamics of Mn_(3)Pt thin film under magnetic fields using atomistic spin dynamic *** study provides a reliable method for detecting Néel vector of noncollinear antiferromagnets through the tunnel magnetoresistance effect and may pave its way for potential applications in antiferromagnetic memory devices.

关键词： tunneling magnetoresistance momentum

Enhanced conductivity and weakened magnetism in Pb-doped Sr2IrO4

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Chinese Physics B 2024年第1期33卷 696-701页

作者：岳智来甄伟立牛瑞焦珂珂朱文卡皮雳张昌锦 High Magnetic field Laboratory Hefei Institutes of Physical ScienceChinese Academy of Sciences science Island Branch of Graduate School University of Science and Technology of China Collaborative Innovation center of Advanced Microstructures Nanjing University

Group IV element Pb has been selected as the dopant to dope at the Sr site of Sr2IrO4. It is exciting to find that the single-phase crystal structure could be maintained with a high Pb doping level of up to x=0.3 in Sr2-xPbxIrO4. The mapping data obtained from energy-dispersive x-ray spectroscopy analyses give solid evidence that the Pb ions are uniformly distributed in the Sr2IrO4matrix. The incorporation of Pb leads to a moderate depression of the canted antiferromagnetic ordering state. The electrical conductivity could be greatly enhanced when the Pb doping content is higher than x=*** present results give a fresh material base to explore new physics in doped Sr2IrO4systems.

关键词： iridates doping conductivity magnetism

Hole mobility enhancement in monolayer WSe2 p-type transistors through molecular doping

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science China(Information sciences) 2024年第6期67卷 207-213页

作者： Shiyuan LIU Xiong XIONG Xin WANG Xinhang SHI Ru HUANG Yanqing WU School of Integrated Circuits and Beijing Advanced Innovation center for Integrated Circuits Peking University Wuhan National High Magnetic field center and School of Integrated Circuits Huazhong University of Science and Technology

Two-dimensional （2D） transition metal dichalcogenide （TMDC） semiconductor materials exhibit extraordinary electrical properties,holding promise for the realization of next-generation complementary metal-oxide-semiconductor （CMOS） devices at ultimate ***,constrained by effective device doping strategies,the hole mobility and device performance of tungsten diselenide （WSe2） p-type transistors,especially monolayer chemical vapor deposition （CVD）-grown WSe2,have not met *** this paper,an effective performance enhancement of monolayer WSe2p-type transistor was achieved through a molecular doping *** monolayer WSe2directly on SiO2back-gated substrates and leveraging energy band alignment design,4-nitrobenzenediazonium tetrafluoroborate （4-NBD） molecular dopant with a concentration of 10 m M was utilized to modulate the Fermi level position of monolayer WSe2for hole *** devices demonstrated a more than 98%increase in hole mobility,reaching up to 97 cm2·V-1·s-1while maintaining the current on/off ratio of *** p-type WSe2transistors with 1μm channel length exhibit a high drive current surpassing 176μA·μm-1,exceeding previous CVD-WSe2devices with similar channel *** straightforward and effective approach to improving the electrical performance of WSe2transistors paves the way for advanced logic technologies based on transition metal dichalcogenide semiconductors.

关键词： CVD-grown WSe$_2$ molecular doping 4-NBD p-type transistors hole mobility

Unravelling the role of the combined effect of metallic charge transfer channel and SiO_(x) overlayer in the Zr/Si-Fe_(2)O_(3):Au:SiO_(x) nanorod arrays to boost photoelectrochemical water splitting

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Journal of Energy Chemistry 2024年第3期90卷 370-379,I0009页

作者： Tae Sik Koh Periyasamy Anushkkaran Love Kumar Dhandole Mahadeo A.Mahadik Weon-Sik Chae Hyun Hwi Lee Sun Hee Choi Jum Suk Jang Division of Biotechnology SafetyEnvironment and Life Science InstituteCollege of Environmental and Bioresource SciencesJeonbuk National UniversityIksan 54896Republic of Korea Department of Integrative Environmental Biotechnology College of Environmental and Bioresource SciencesJeonbuk National UniversityIksan 54596Republic of Korea Extreme Materials Research center Korea Institute of Science and Technology(KIST)Seoul 02792Republic of Korea Daegu center Korea Basic Science InstituteDaegu 41566Republic of Korea Pohang Accelerator Laboratory Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea

Hematite(α-Fe_(2)O_(3)) based photoanodes have been extensively studied due to various intriguing features that make them viable candidates for a photoelectrochemical(PEC) water splitting ***,we propose a Zr-doped Fe_(2)O_(3) photoanode decorated with facilely spin-coated Au nanoparticles(NPs) and microwave-assisted attached Si co-doping in conjunction with a SiO_(x) overlayer that displayed a remarkable photocurrent density of 2.01 mA/cm^(2) at 1.23 V *** kinetic dynamics at the photoelectrode/-electrolyte interface was examined by employing systematic electrochemical *** Au NPs played a dual role in increasing PEC water ***,the Schottky interface that was formed between Au NPs and Zr-Fe_(2)O_(3) lectrode ensured the prevention of electron flow from the photoanode to the metal,increasing the number of available charges as well as suppressing surface charge ***,Au extracted photoholes from the bulk of the Zr-Fe_(2)O_(3) and transported them to the outer SiO_(x) overlayer,while the SiO_(x) overlayer efficiently collected the photoholes and promoted the hole injection into the ***,Si co-doping enhanced bulk conductivity by reducing bulk charge transfer resistance and improving charge carrier *** study outlines a technique to design a metallic charge transfer path with an overlayer for solar energy conversion.

关键词： Hematite Microwave attachment Au nanoparticles SiO_(x) overlayer Water splitting

Pulse repetition rate effect on the plasma inside femtosecond laser filament in air

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Chinese Optics Letters 2024年第1期22卷 135-140页

作者：尹富康王铁军刘尧香龙娟魏迎霞朱斌周凯南冷雨欣 State Key Laboratory of High field Laser Physics Shanghai Institute of Optics and Fine Mechanics and CAS Center for Excellence in Ultra-intense Laser ScienceChinese Academy of SciencesShanghai 201800China center of Materials science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Laser Fusion Research center and science&Technology on Plasma Physics Laboratory China Academy of Engineering PhysicsMianyang 621999China

The characteristics of plasmas play an important role in femtosecond laser filament-based *** analysis is used to experimentally investigate the plasma density and its temperature of the air filament under different pulse repetition *** our experiments,the measured average plasma density of the filament is 1.54×10^(17)cm^(-3)and the temperature of the plasma is about 5100 K under 100 Hz pulse repetition *** plasma density decreases to1.43×10^(17)cm^(-3)and the temperature increases to 6230 K as the pulse repetition rate increases to 1000 *** experimental observation agrees with the numerical simulation by solving the nonlinear Schr?dinger equations with repetition rate related“low density hole”correction.

关键词： femtosecond laser filamentation cumulative effects electron density

Suppression of nanosecond prepulses from regenerative amplifier and multipass amplifiers in the SULF-1PW laser

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Chinese Optics Letters 2024年第5期22卷 75-79页

作者：白培乐张宗昕王新亮钱佳毅朱佳诚吴分翔胡家兵杨晓骏归佳彦陆效明刘彦祺许毅梁晓燕冷雨欣李儒新 State Key Laboratory of High field Laser Physics and CAS center for Excellence in Ultra-intense Laser science Shanghai Institute of Optics and Fine Mechanics(SIOM)Chinese Academy of Sciences(CAS)Shanghai 201800China center of Materials science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

In this research,we report the latest progress in the suppression of nanosecond prepulses from regenerative amplifier and multipass amplifiers in the SULF-1PW *** prepulse generated from the Pockels cell(PC)in a regenerative amplifier is delay-shifted by enlarging the distance between the PC and the nearby cavity mirror,and then removed by the extra pulse pickers outside the regenerative *** prepulses arising from multipass amplifiers are also further suppressed by adopting a novel amplifier configuration and properly rotating the Ti:sapphire *** the optimizations,the temporal contrast on a nanosecond time scale is promoted to be better than a contrast level of 10^(-9).This research can provide beneficial guidance for the suppression of nanosecond prepulses in the high-peak-power femtosecond laser systems.

关键词： high-peak-power femtosecond laser nanosecond prepulses temporal contrast

Pressure-induced magnetic phase and structural transition in SmSb2

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Chinese Physics B 2024年第6期33卷 484-489页

作者：李涛王舒阳陈绪亮陈春华房勇杨昭荣 science Island Branch of Graduate School University of Science and Technology of China Anhui Key Laboratory of Low-Energy Quantum Materials and Devices High Magnetic Field LaboratoryHFIPS Chinese Academy of Sciences Jiangsu Laboratory of Advanced Functional Materials Department of Physics Changshu Institute of Technology Institutes of Physical science and Information Technology Anhui University Collaborative Innovation center of Advanced Microstructures

Motivated by the recent discovery of unconventional superconductivity around a magnetic quantum critical point in pressurized CeSb2,here we present a high-pressure study of an isostructural antiferromagnetic（AFM） SmSb2through electrical transport and synchrotron x-ray diffraction *** PC～2.5 GPa,we found a pressure-induced magnetic phase transition accompanied by a Cmca→P4/nmm structural phase *** the pristine AFM phase below PC,the AFM transition temperature of SmSb2is insensitive to pressure;in the emergent magnetic phase above PC,however,the magnetic critical temperature increases rapidly with increasing *** addition,at ambient pressure,the magnetoresistivity（MR） of SmSb2increases suddenly upon cooling below the AFM transition temperature and presents linear nonsaturating behavior under high field at 2 *** increasing pressure above PC,the MR behavior remains similar to that observed at ambient pressure,both in terms of temperature-and field-dependent *** leads us to argue an AFM-like state for SmSb2above *** the investigated pressure of up to 45.3 GPa and the temperature of down to 1.8 K,we found no signature of superconductivity in SmSb2.

关键词： antiferromagnet high pressure magnetoresistivity structural transition

Inversion of O_(2) 1.27 μm nightglow emissions: A climatological analysis using satellite Limb-Viewed spectra and Harmonic analysis method

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Earth and Planetary Physics 2024年第4期8卷 632-640页

作者： YiYi Sui YaJun Zhu QiuYu Chen MaoSheng He JiYao Xu State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of sciences Beijing 100190China Key Laboratory of Solar Activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Hainan National field science Observation and Research Observatory for Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China

This study employs a linear inversion algorithm to retrieve volume emission rates(VERs)of molecular O_(2) nightglow at 1.27μm,utilizing Limb-Viewed spectra obtained from the SCanning Imaging Absorption spectroMeter for Atmospheric for CHartographY(SCIAMACHY)payload on board the Envisat *** retrieved results are compared with VERs data from the SABER payload on the Thermosphere Ionosphere Mesosphere Energetics and Dynamics(TIMED)satellite,exhibiting *** will help to facilitate accurate revelation of spatial distribution and periodic variation in O_(2) *** are extracted monthly within the altitude range of 75-110 km from 2002 to 2012,yielding a climatology of spatial and temporal *** meridional structure exhibits two maxima,at the equator and at 45°*** August and October,the VERs exhibit a meridional bimodal structure,with the weaker one above the equator and the stronger one above 45°*** April,the VERs reach their annual ***,harmonic analysis reveals significant temporal variations on different *** emission shows characteristics of annual and semi-annual variation,and a non-linear long-term trend associated with solar cycle activity.

关键词： VERs O_(2)1.27μm nightglow SCIAMACHY

Quantum control for time-dependent noise by inverse geometric optimization

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science China(Physics,Mechanics & Astronomy) 2024年第9期Mechanics & Astronomy) .卷 55-61页

作者： Xiaodong Yang Yingcheng Li Ran Liu Xinfang Nie Tao Xin Dawei Lu Jun Li Institute of Quantum Precision Measurement State Key Laboratory of Radio Frequency Heterogeneous IntegrationCollege of Physics and Optoelectronic EngineeringShenzhen University State Key Laboratory of Surface Physics Department of PhysicsCenter for Field Theory and Particle Physicsand Institute for Nanoelectronic Devices and Quantum ComputingFudan University Shenzhen Institute for Quantum science and Engineering and Department of Physics Southern University of Science and Technology Guangdong Provincial Key Laboratory of Quantum science and Engineering Southern University of Science and Technology Quantum science center of Guangdong-Hong Kong-Macao Greater Bay Area(Guangdong)

Quantum systems are exceedingly difficult to engineer because they are sensitive to various types of noises. In particular, timedependent noises are frequently encountered in experiments but how to overcome them remains a challenging problem. In this work, we propose a flexible robust control technique to resist time-dependent noises based on inverse geometric optimization working in the filter-function formalism. The basic idea is to parameterize the control filter function geometrically and minimize its overlap with the noise spectral density. This then effectively reduces the noise susceptibility of the controlled system evolution. We show that the proposed method can produce high-quality robust pulses for realizing desired quantum evolutions under realistic noise models. Also, we demonstrate this method in examples including dynamical decoupling and quantum sensing protocols to enhance their performances.

关键词： time-dependent noise robust control quantum gates and states dynamical decoupling quantum sensing

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