检索结果-南通市图书馆

Electrically-driven ultrafast out-of-equilibrium light emission from hot electrons in suspended graphene/hBN heterostructures

在线全文

学校读者我要写书评

暂无评论

International Journal of Extreme Manufacturing 2024年第1期6卷 328-338页

作者： Qiang Liu Wei Xu Xiaoxi Li Tongyao Zhang Chengbing Qin Fang Luo Zhihong Zhu Shiqiao Qin Mengjian Zhu Kostya S Novoselov College of Advanced Interdisciplinary Studies&Hunan Provincial Key Laboratory of Novel Nano-optoelectronic Information Materials and Devices National University of Defense TechnologyChangshaHunan 410073People’s Republic of China Nanhu Laser Laboratory National University of Defense TechnologyChangshaHunan 410073People’s Republic of China State Key Laboratory of Quantum optics and Quantum optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006People’s Republic of China Collaborative Innovation Center of Extreme optics Shanxi UniversityTaiyuan 030006People’s Republic of China State Key Laboratory of Quantum optics and Quantum optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006People’s Republic of China institute for Functional Intelligent Materials National University of SingaporeSingapore 117544Singapore Department of Materials Science and Engineering National University of SingaporeSingapore 117575Singapore

Nanoscale light sources with high speed of electrical modulation and low energy consumption are key components for nanophotonics and *** record-high carrier mobility and ultrafast carrier dynamics of graphene make it promising as an atomically thin light emitter which can be further integrated into arbitrary platforms by van der Waals ***,due to the zero bandgap,graphene is difficult to emit light through the interband recombination of carriers like conventional ***,we demonstrate ultrafast thermal light emitters based on suspended graphene/hexagonal boron nitride(Gr/hBN)*** in biased graphene are significantly heated up to 2800 K at modest electric fields,emitting bright photons from the near-infrared to the visible spectral *** eliminating the heat dissipation channel of the substrate,the radiation efficiency of the suspended Gr/hBN device is about two orders of magnitude greater than that of graphene devices supported on SiO2or *** demonstrate that hot electrons and low-energy acoustic phonons in graphene are weakly coupled to each other and are not in full thermal *** cooling ofhigh-temperature hot electrons to low-temperature acoustic phonons is enabled by the significant near-field heat transfer at the highly localized Gr/hBN interface,resulting in ultrafast thermal emission with up to 1 GHz bandwidth under electrical *** is found thatsuspending the Gr/hBN heterostructures on the SiO2trenches significantly modifies the light emission due to the formation of the optical cavity and showed a~440%enhancement inintensity at the peak wavelength of 940 nm compared to the black-body thermal *** demonstration of electrically driven ultrafast light emission from suspended Gr/hBNheterostructures sheds the light on applications of graphene heterostructures in photonicintegrated circuits,such as broadband light sources and ultrafast thermo-optic phase modulat

关键词： suspended graphene ultrafast light emitter van der Waals heterostructures thermal radiation electron–phonon interaction

Mobility edges and localization characteristics in one-dimensional quasiperiodic quantum walk

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第6期33卷 156-160页

作者：崔鑫辉王慧敏李志坚 institute of Theoretical Physics State Key Laboratory of Quantum Optics and Quantum DevicesShanxi UniversityTaiyuan 030006China

We construct a one-dimensional quasiperiodic quantum walk to investigate the localization–delocalization *** inverse participation ratio and Lyapunov exponent are employed as two indexes to determine the mobility edge, a critical energy to distinguish the energy regions of extended and localized states. The analytical solution of mobility edge is obtained by the Lyapunov exponents in global theory, and the consistency of the two indexes is confirmed. We further study the dynamic characteristics of the quantum walk and show that the probabilities are localized to some specific lattice sites with time evolution. This phenomenon is explained by the effective potential of the Hamiltonian which corresponds to the phase in the coin operator of the quantum walk.

关键词： quantum walk mobility edges quasiperiodicity

Interplay between topology and localization on superconducting circuits

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第6期33卷 240-246页

作者：关欣霍炳燕陈刚 Department of Materials and Chemical Engineering Taiyuan UniversityTaiyuan 030032China State Key Laboratory of Quantum optics and Quantum optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Extreme optics Shanxi UniversityTaiyuan 030006China School of Physics Zhengzhou UniversityZhengzhou 450001China

Topological insulators occupy a prominent position in the realm of condensed matter physics. Nevertheless, the presence of strong disorder has the potential to disrupt the integrity of topological states, leading to the localization of all *** study delves into the intricate interplay between topology and localization within the one-dimensional Su–Schrieffer–Heeger(SSH) model, which incorporates controllable off-diagonal quasi-periodic modulations on superconducting *** the application of external alternating current(ac) magnetic fluxes, each transmon undergoes controlled driving,enabling independent tuning of all coupling strengths. Within a framework of this model, we construct comprehensive phase diagrams delineating regions characterized by extended topologically nontrivial states, critical localization, and coexisting topological and critical localization phases. The paper also addresses the dynamics of qubit excitations, elucidating distinct quantum state transfers resulting from the intricate interplay between topology and localization. Additionally, we propose a method for detecting diverse quantum phases utilizing existing experimental setups.

关键词： topology localization superconducting circuits

Remote sensing of air pollution incorporating integrated-path differential-absorption and coherent-Doppler lidar

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第1期31卷 594-601页

作者： Ze-hou Yang Yong Chen Chun-li Chen Yong-ke Zhang Ji-hui Dong Tao Peng Xiao-feng Li Ding-fu Zhou School of Physics Beijing Institute of TechnologyBeijing 100081China Southwest institute of Technical Physics Chengdu 610041SichuanChina School of optics and Photonics Beijing Institute of TechnologyBeijing 100081China

An innovative complex lidar system deployed on an airborne rotorcraft platform for remote sensing of atmospheric pollution is proposed and *** system incorporates integrated-path differential absorption lidar(DIAL) and coherent-doppler lidar(CDL) techniques using a dual tunable TEA CO_(2)laser in the 9—11 μm band and a 1.55 μm fiber *** combining the principles of differential absorption detection and pulsed coherent detection,the system enables agile and remote sensing of atmospheric *** static tests validate the system’s real-time detection capabilities,including the measurement of concentration-path-length product(CL),front distance,and path wind speed of air pollution plumes over long distances exceeding 4 *** experiments is conducted with the *** of the pollutant concentration and the wind field is carried out in an approximately 1 km slant range over scanning angle ranges from 45°to 65°,with a radial resolution of 30 m and10 *** test results demonstrate the system’s ability to spatially map atmospheric pollution plumes and predict their motion and dispersion patterns,thereby ensuring the protection of public safety.

关键词： Differential absorption LIDAR Coherent Doppler lidar Remoting sensing Atmospheric pollution

Two-dimensional localized modes in nonlinear systems with linear nonlocality and moiré lattices

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2024年第4期19卷 265-273页

作者： Xiuye Liu Jianhua Zeng Center for Attosecond Science and Technology State Key Laboratory of Transient Optics and PhotonicsXi’an Institute of Optics and Precision Mechanics of Chinese Academy of SciencesXi’an 710119China University of Chinese Academy of Sciences Beijing 100049China Collaborative lnnovation Center of Extreme optics Shanxi UniversityTaiyuan 030006China

Periodic structures structured as photonic crystals and optical lattices are fascinating for nonlinear waves engineering in the optics and ultracold atoms ***éphotonic and optical lattices—two-dimensional twisted patterns lie somewhere in between perfect periodic structures and aperiodic ones—are a new emerging investigative tool for studying nonlinear localized waves of diverse ***,a theory of two-dimensional spatial localization in nonlinear periodic systems with fractional-order diffraction(linear nonlocality)and moiréoptical lattices is ***,the flat-band feature is well preserved in shallow moiréoptical lattices which,interact with the defocusing nonlinearity of the media,can support fundamental gap solitons,bound states composed of several fundamental solitons,and topological states(gap vortices)with vortex charge s=1 and 2,all populated inside the finite gaps of the linear Bloch-wave *** the linear-stability analysis and direct perturbed simulations,the stability and instability properties of all the localized gap modes are surveyed,highlighting a wide stability region within the first gap and a limited one(to the central part)for the third *** findings enable insightful studies of highly localized gap modes in linear nonlocality(fractional)physical systems with shallow moirépatterns that exhibit extremely flat bands.

关键词： moiréoptical lattices gap solitons and vortices ultracold atoms Gross-Pitaevskii/nonlinear fractional Schrödinger equation nonlinear fractional systems

Real-time monitoring of oxygenation in deep brain tissue using a wireless photoelectric probe

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Materials 2024年第4期67卷 1361-1362页

作者： Hao Pang Qilin Hua Guozhen Shen School of Integrated Circuits and electronics Beijing Institute of TechnologyBeijing 100084China institute of Flexible electronics Beijing Institute of TechnologyBeijing 102488China

Oxygen(O2) supply to the brain is of utmost importance for human health, as cerebral hypoxia can result in irreversible brain damage. Neurodegenerative diseases, such as epilepsy, are closely associated with cerebral hypoxia [1,2]. Real-time monitoring of cerebral oxygenation holds significant value in neuroscience research and clinical diagnostics [3–10].

关键词： epilepsy cerebral diseases

同方期刊数据库

Generation of 160 nm vacuum ultraviolet light at 82 MHz in a KBBF crystal by the fifth-harmonic of a Ti:sapphire laser

在线全文

学校读者我要写书评

暂无评论

Chinese optics Letters 2024年第5期22卷 95-99页

作者：张赟汪丽蓉 Department of Engineering Science The University of Electro-CommunicationsTokyo 182-8585Japan State Key Laboratory of Quantum optics and Quantum optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Extreme optics Shanxi UniversityTaiyuan 030006China

We report the generation of quasi-cw vacuum ultraviolet(VUV)light at 160 nm with a repetition rate of 82 MHz by two second-harmonic generations and one sum frequency *** VUV laser light is produced as a fifth-harmonic generation of a mode-locked ps Ti:sapphire laser system by successive stages with nonlinear crystals of LBO and KBBF.A stable generation of laser light at 200 nm for more than 6 h is the most important step for obtaining the generation of light at a wavelength of 160 nm.

关键词： vacuum ultraviolet light second harmonic generation sum frequency mixing

High-Performance Organic Field-Effect Transistors Based on Two-Dimensional Vat Orange 3 Crystals

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2024年第2期41卷 122-128页

作者：闫宁熊志仁秦成兵李小茜 State Key Laboratory of Quantum optics and Quantum optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Extreme optics Shanxi UniversityTaiyuan 030006China State Key Laboratory of Quantum optics and Quantum optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006China

The exploration and research of low-cost,environmentally friendly,and sustainable organic semiconductor materials are of immense significance in various fields,including electronics,optoelectronics,and energy ***,these semiconductors have almost poor charge transport properties,which range from∼10^(−4) cm^(2)·V^(−1)·s^(−1) to∼10^(−2) cm^(2)·V^(−1)·s^(−1).Vat orange 3,as one of these organic semiconductors,has great potential due to its highly conjugated *** obtain high-quality multilayered Vat orange 3 crystals with two-dimensional(2D)growth on h-BN surfaces with thickness of 10–100 nm using physical vapor ***’s results confirm the stability of the chemical structure of Vat orange 3 during ***,by leveraging the structural advantages of 2D materials,an organic field-effect transistor with a 2D vdW vertical heterostructure is further realized with h-BN encapsulation and multilayered graphene contact electrodes,resulting in an excellent transistor performance with On/Off ratio of 104 and high field-effect mobility of 0.14 cm^(2)·V^(−1)·s^(−1).Our results show the great potential of Vat orange 3 with 2D structures in future nano-electronic ***,we showcase an approach that integrates organic semiconductors with 2D materials,aiming to offer new insights into the study of organic semiconductors.

关键词： transistor orange semiconductors

A Confined Two-peaked Solar Flare Observed by EAST and SDO

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第4期24卷 71-83页

作者： Liang Zhang Ruisheng Zheng Zhike Xue Changhui Rao Qing Lin Zhimao Du Jiawen Yao Libo Zhong Yao Chen institute of Space Sciences Shandong UniversityWeihai 264209China Yunnan Key Laboratory of the Solar physics and Space Science Kunming 650011China institute of Frontier and Interdisciplinary Science.Shandong University Qingdao266237China institute of optics and electronics Chinese Academy of SciencesChengdu 610209China National Laboratory on Adaptive optics Chengdu610209China University of Chinese Academy of Sciences Beijing 100049China Shanghai Astronomy Museum Shanghai201306China

The solar flare is one of the most violent explosions,and can disturb the near-Earth space *** for commonly single-peaked solar flares in soft X-ray,some special flares show intriguing a two-peak feature that is deserved much more ***,we reported a confined two-peaked solar flare and analyzed the associated eruptions using high-quality observations from Educational Adaptive-optics Solar Telescope and Solar Dynamics *** the flare,a magnetic flux rope(MFR)formed through partially tether-cutting reconnection between two sheared *** flare occurred after the MFR eruption that was confined by the overlying strong ***,a small underlying filament immediately erupted,which was possibly destabilized by the flare *** successive eruptions were confirmed by the analysis of the emission measure and the reconnection ***,we suggest that the two peaks of the confined solar flare are corresponding to two episodes of magnetic reconnection during the successive eruptions of the MFR and the underlying filament.

关键词： Sun:activity Sun:corona Sun:flares Sun:magnetic fields Sun:filaments prominences Online material:animations