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Plasmonics for solid-state lighting: enhanced excitation and directional emission of highly efficient light sources

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Light(Science & Applications) 2013年第1期2卷 163-169页

作者： Gabriel Lozano Davy J Louwers Said RK Rodrı´guez Shunsuke Murai Olaf TA Jansen Marc A Verschuuren Jaime Gomez Rivas Center for Nanophotonics FOM Institute AMOLFc/o Philips Research LaboratoriesEindhovenThe Netherlands Philips research laboratories EindhovenThe Netherlands Department of Material Chemistry Graduate School of EngineeringKyoto UniversityKyotoJapan COBRA research Institute Eindhoven University of TechnologyEindhovenThe Netherlands

Light sources based on reliable and energy-efficient light-emitting diodes (LEDs) are instrumental in the development of solid-statelighting (SSL). Most research efforts in SSL have focused on improving both the intrinsic quantum efficiency (QE) and the stability oflight emitters. For this reason, it is broadly accepted that with the advent of highly efficient (QE close to 1) and stable emitters, thefundamental research phase of SSL is coming to an end. In this study, we demonstrate a very large improvement in SSL emission (above70-fold directional enhancement for p-polarized emission and 60-fold enhancement for unpolarized emission) using nanophotonicstructures. This is attained by coupling emitters with very high QE to collective plasmonic resonances in periodic arrays of aluminumnanoantennas. Our results open a new path for fundamental and applied research in SSL in which plasmonic nanostructures are able tomold the spectral and angular distribution of the emission with unprecedented precision.

关键词： diffraction fluorescence LED nanophotonics plasmonics

Estimation of electron mobility of n-doped 4,7-diphenyl-1,10-phenanthroline using space-charge-limited currents

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Journal of Semiconductors 2009年第11期30卷 63-66页

作者：希扎尔.乌尔.哈克鲁富翰蒋雪茵张志林张小文张良李俊 School of Materials Science and Engineering Shanghai University Key laboratories of advanced Display and System Applications Ministry of EducationShanghai University

The electron mobilities of 4, 7-diphenyl-1, 10-phenanthroline （BPhen） doped 8-hydroxyquinolinatolithium （Liq） at various thicknesses （50-300 nm） have been estimated by using space-charge-limited current measurements. It is observed that the electron mobility of 33 wt% Liq doped BPhen approaches its true value when the thickness is more than 200 rim. The electron mobility of 33 wt% Liq doped BPhen at 300 nm is found to be -5.2 × 10^-3 cm^2/（V.s）（at 0.3 MV/cm） with weak dependence on electric field, which is about one order of magnitude higher than that of pristine BPhen （3.4 × 10^-4 cm^2/（V.s）） measured by SCLC. For the typical thickness of organic light-emitting devices, the electron mobility of doped BPhen is also investigated.

关键词： doping electron mobility SCLC 8-hydroxyquinolinonate-lithium (Liq)

Low-energy electronic states of carbon nanocones in an electric field

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Nano-Micro Letters 2010年第2期2卷 121-125页

作者： Jun-Liang Chen Ming-Horng Su Chi-Chuan Hwang Jian-Ming Lu Chia-Chang Tsai Department of Mechanical Engineering Wu Feng Institute of Technology Department of Fire Science Wu Feng Institute of Technology Department of Engineering Science National Cheng Kung University advanced Networking Business Unit National Center for High-Performance Computing National Applied Research Laboratories Institute of Atomic and Molecular Sciences Academia Sinica

The low-energy electronic states and energy gaps of carbon nanocones in an electric field are studied using a single-?-band tight-binding model. The analysis considers five perfect carbon nanocones with disclination angles of 60°, 120°, 180°, 240° and 300°, respectively. The numerical results reveal that the low-energy electronic states and energy gaps of a carbon nanocones are highly sensitive to its geometric shape(i.e. the disclination angle and height), and to the direction and magnitude of an electric field. The electric field causes a strong modulation of the state energies and energy gaps of the nanocones, changes their Fermi levels, and induces zero-gap transitions. The energy-gap modulation effect becomes particularly pronounced at higher strength of the applied electric field, and is strongly related to the geometric structure of the nanocone.

关键词： Low-energy electronic states Carbon Nanocones Electric field

Mitigating set-stuck failure in 3D phase change memory: substituting square pulses with surge pulses

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Science China(Information Sciences) 2024年第5期67卷 295-301页

作者： Ninghua LI Wang CAI Jun XIANG Hao TONG Weiming CHENG Xiangshui MIAO School of Integrated Circuits Huazhong University of Science and Technology Hubei Yangtze Memory laboratories Hubei Institute of Measurement and Testing technology

In the devices that integrate phase change memory(PCM) and ovonic threshold switching(OTS),the OTS threshold voltage often surpasses the RESET operation voltage of PCM. The conventional application of square pulses hinders the successful completion of the SET operation in these integrated devices. To address this challenge, a novel pulse called the surge pulse is introduced, which comprises a high amplitude pulse for OTS activation and a low amplitude pulse for PCM operation. By employing COMSOL simulation,the operational effectiveness of both square pulses and surge pulses is validated. Test results reveal that using a square pulse to operate the integrated device accelerates the occurrence of SET-stuck failure(SSF).In contrast, the surge pulse enables the integrated device to operate for at least 1000 cycles while preserving the essential cyclic characteristics. Additionally, an investigation into the overshoot component of the surge pulse is conducted, revealing that an increase in overshoot amplitude and pulse width also accelerates the emergence of SSF. By applying the theory of ion migration induced by the electric field, the root cause of SSF in integrated devices is explained, and the accuracy of the theory is validated through the application of a reverse pulse. In summary, this study elucidates the rationality of replacing the square pulse with a surge pulse, presenting a superior approach for operating PCM and OTS integrated devices.

关键词： surge pulse phase change memory (PCM) integration SET-stuck failure (SSF) square pulse

Slicing capacity-centered mode selection and resource optimization for network-assisted full-duplex cell-free distributed massive MIMO systems

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Science China(Information Sciences) 2024年第1期67卷 203-220页

作者： Jie WANG Jiamin LI Pengcheng ZHU Dongming WANG Hongbiao ZHANG Yue HAO Bin SHENG National Mobile Communications research Laboratory Southeast University 2. Purple Mountain Laboratories China Mobile research Institute

Network-assisted full-duplex(NAFD) cell-free distributed massive multiple-input multipleoutput(MIMO) systems enable uplink(UL) and downlink(DL) communications within the same timefrequency resources,which potentially reduce latency by avoiding the overhead of switching UL/DL ***,how to choose UL/DL modes remains an important factor affecting system *** the dramatic increase in the number of users and access points(APs),massive access brings significant overhead in the mode ***,the different quality of service(QoS) among users also makes the effective utilization of resources *** one of the most promising technologies in sixth-generation(6G),network slicing enables the adaptive configuration of limited UL/DL resources through the resource isolation assisted NAFD ***,we propose a slicing capacity-centered *** this scheme,APs are motivated by slicing requirements and associated slices to form different *** mode selection and resource allocation are performed within each subsystem to reduce overhead and improve resource *** implement this scheme efficiently,a double-layer deep reinforcement learning(DRL)mechanism is used to realize the joint optimization of mode selection and resource *** results show that the slicing capacity-centered scheme can effectively improve resource utilization and reduce overhead.

关键词： network-assisted full-duplex network slicing mode selection resource optimization deep reinforcement learning

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Dynamic range criterion of THz spectrum for amino acids measurements

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Frontiers of Optoelectronics 2009年第3期2卷 239-243页

作者： Zhaohui ZHANG Zuxing ZHANG Yixin YIN Yuko UENO Rakchanok RUNGSAWANG Katsuhiro AJITO Information Engineering School University of Science and Technology Beijing NTT Basic research laboratories

Terahertz(THz) absorption spectra have been applied to measure the compositions of amino acid samples. Because the concentration information about a specific composition is involved in its spectrum, keeping the spectrum length and dynamic range as wide as possible is essential for precise measurements. It is well known that a spectrum is always contaminated by apparatus noises. In this paper, we present a criterion for noise cutting based on wavelet transform, which usually extends the range determined by traditional threshold criterion. Finally, the improvement on measurement precision shows the validity of the new criterion.

关键词： terahertz (THz) time domain spectroscopy absorption spectrum dynamic range wavelet transform quantitative analysis amino acids

Experimental Investigation of Capacity Control Scheme on System Performance for a Machine Tool Cooler

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Chinese Journal of Mechanical Engineering 2011年第3期24卷 333-339页

作者： WANG Fujen CHANG Tongbou KAO Jianwei LEE Haochung Department of Refrigeration Air Conditioning and Energy Engineering Chin-Yi University of Technology Taiehung 411 Taiwan China Department of Mechanical Engineering Southern Taiwan University Tainan 710 Taiwan China Energy and Environment research laboratories Industrial Technology Research Institute Hsinchu 310 Taiwan China

Highly accurate manufacture in machining industry can only be obtained with precise temperature control of the coolant （oil or water）.Machine tool with more accurate,stable and advanced the precision of the working component cannot be developed without appropriate ***,the machine tool coolers are facing the control hunting of cooling temperature and the dramatic variation of heat load in high-accuracy *** main objective of this study is to evaluate the influence of the hot-gas by-pass scheme and suction regulation for capacity control of a machine tool cooler *** this study,experimental investigation on both hot-gas by-pass scheme and suction valve regulation for capacity control has been *** of using capillary tube and thermostatic expansion valve along with different capacity control scheme have been investigated extensively in an environmental testing *** performance and power consumption of the cooler system have been measured and analyzed as well by comparing with different opening percentage of throttling valve under specific coolant *** experimental results reveal that the power consumption will reduce slightly by capacity control using the hot-gas by-pass scheme but the coefficient of performance （COP） of the overall system will *** coolant temperature will result in higher compressor power consumption as *** conducting suction valve regulating for capacity control,energy-saving at 10%-12% can be obtained by using thermostatic expansion valve under different evaporator *** also reveals that suction valve regulation along with adequate choice of thermostatic expansion valve can provide alternative choice for steady capacity control and substantial *** proposed cooler systems with different capacity control schemes are not only more cost-effective than inverter driven system,but also can perform energy-saving and precise temperature control specific for high-accur

关键词： machine tool cooler hot-gas by-pas suction regulation capacity control

The Genesis Mechanism of the Mantle Fluid Action and Evolution in the Ore-Forming Process: A Case Study of the Laowangzhai Gold Deposit in Yunnan, China

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Acta Geologica Sinica(English Edition) 2012年第3期86卷 608-618页

作者： LIU Xianfan LI Chunhui LU Qiuxia DENG Biping SONG Xiangfeng ZHAO Fufeng CHU Yating XIAO Jixiong YI Liwen HUANG Yupeng Institute of Earth Science Chengdu University of TechnologyChengdu 610059China State Key laboratories for Mineral Deposits research Nanjing UniversityNanjing 210093China

Based on petrological studies of the wall rocks, mineralizing rocks, ores and veins from the Laowangzhai gold deposit, it is discovered that along with the development of silication, carbonation and sulfidation, a kind of black opaque ultra-microlite material runs through the spaces between grains, fissures and cleavages. Under observations of the electron microprobe, scanning electronic microscopy and energy spectrum, this kind of ultra-microlite material is confirmed to consist of ultra microcrystalline quartz, silicate, sulfides and carbonates, as well as rutile, scheelite and specularite （magnetite）, showing characters of liquation by the analyses of SEM and energy spectrum. The coexistence of immiscibility and precipitating co-crystallization strongly suggests that the mineralizing fluid changed from the melt to the hydrothermal fluid. Combined with the element geochemical researches, it is realized that the ultra-microlite aggregate is the direct relics of the mantle fluid behaving like a melt and supercritical fluid, which goes along with the mantle-derived magma and will escape from the magma body at a proper time. During the alteration process, the nature of the mantle fluid changed and it is mixed with the crustal fluid, which are favorable for mineralization in the Loawangzhai gold deposit.

关键词： micro-petrography black opaque material ultra-microlite aggregate mantle fluid process and evolution the Laowangzhai gold deposit

Achieving full mutualism with massive passive devices for multiuser MIMO symbiotic radio

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Science China(Information Sciences) 2024年第9期67卷 196-212页

作者： Jingran XU Zhuoyin DAI Yong ZENG Shi JIN Tao JIANG National Mobile Communications research Laboratory Southeast University Purple Mountain laboratories research Center of 6G Mobile Communications School of Cyber Science and Engineering and Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology

Symbiotic radio(SR) is one of the attractive communication technologies to facilitate largescale Internet of Things(IoT) connections with enhanced energy and spectrum efficiency, where passive backscatter devices(BDs) modulate their information over the radio frequency(RF) signals emitted by the active primary transmitters(PTs). Meanwhile, the primary transmission can be strengthened with the additional multipaths created by BDs. To capitalize to a greater extent on the mutualism relationship between the two types of communication, this paper studies multiple-input multiple-output(MIMO) SR communication systems including multiple PTs and massive BDs. We derive the achievable rate expressions of each PT and BD, as well as the sum rate expressions of primary and secondary communication, *** asymptotic analysis is given to derive the active and passive communication rates with a large number of BDs. Furthermore, for the general case with a finite number of BDs, we study the precoding optimization problem to maximize the sum rate of primary communication, while ensuring that the sum rate of secondary communication and the individual rate for each PT and BD in the prescribed active and passive user sets satisfy the specified thresholds. Simulation results are presented to verify the analytical studies.

关键词： multiuser MIMO SR backscattering massive backscatter devices asymptotic analysis active and passive communication