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41.
Manipulable and Hybridized,Ultralow‐Threshold Lasing in a Plasmonic Laser Using Elliptical InGaN/GaN Nanorods 下载免费PDF全文
Tao Tao Ting Zhi Bin Liu Jiangping Dai Zhe Zhuang Zili Xie Peng Chen Fangfang Ren Dunjun Chen Youdou Zheng Rong Zhang 《Advanced functional materials》2017,27(37)
Manipulating stimulated‐emission light in nanophotonic devices on scales smaller than their emission wavelengths to meet the requirements for optoelectronic integrations is a challenging but important step. Surface plasmon polaritons (SPPs) are one of the most promising candidates for sub‐wavelength optical confinement. In this study, based on the principle of surface plasmon amplification by the stimulated emission of radiation (SPASER), III‐Nitride‐based plasmonic nanolaser with hybrid metal–oxide–semiconductor (MOS) structures is designed. Using geometrically elliptical nanostructures fabricated by nanoimprint lithography, elliptical nanolasers able to demonstrate single‐mode and multimode lasing with an optical pumping power density as low as 0.3 kW cm?2 at room temperature and a quality Q factor of up to 123 at a wavelength of ≈490 nm are achieved. The ultralow lasing threshold is attributed to the SPP‐coupling‐induced strong electric‐field‐confinement in the elliptical MOS structures. In accordance with the theoretical and experimental results, the size and shape of the nanorod are the keys for manipulating hybridization of the plasmonic and photonic lasing modes in the SPASER. This finding provides innovative insight that will contribute to realizing a new generation of optoelectronic and information devices. 相似文献
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为了研究真空系统中被加热的蓝宝石衬底应力的变化,利用有限元分析方法,借助ANSYSWorkbench软件仿真了温度场以及应力场,对两种不同结构的加热器及加热工艺参数进行了分析.用多圈钨丝螺旋结构外加抛物面釜的加热器,并改变工作电流,将200℃下温度差异由41.13℃降低至2.33℃,使厚度为2mm、直径40mm的蓝宝石衬底整个圆面内的应力差异由2.11MPa减小为1.56 MPa,应力差异减小了26.1%.结果表明,采用多圈钨丝螺旋结构外加抛物面釜可获得高均匀性的加热器温度场,且当工作电流为12A时,加热的蓝宝石衬底整个表面应力分布均匀.并采用蓝宝石衬底的应力检测结果进行了验证.研究结果对真空系统中被加热的其它材料如GaAs、InGaAs、GaN、Si、石英玻璃等应力分析研究具有一定的借鉴意义. 相似文献
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Xiaohui Chen Niu Niu Dan Li Zicong Zhang Zeyan Zhuang Dingyuan Yan Jiangao Li Zujin Zhao Dong Wang Ben Zhong Tang 《Advanced functional materials》2023,33(8):2211571
Photoactivatable agent is a powerful tool in biomedicine studies due to high-precision spatiotemporal control of light. However, those previously reported agents generally suffer from short wavelength, fluorescence self-quenching effect, and the lack of photosensitizing property, which severely restrict their practical applications. To address these issues, molecular engineering of 1,4-dihydropyridine derivatives is conducted to obtain an optimized agent, namely TPA-DHPy-Py, which exhibits low oxidation potential, high photoactivation efficiency, and excellent type I/II combined photodynamic activity. Concurrently, its photoactivated counterpart is featured by aggregation-induced near-infrared emission and remarkable reactive oxygen species (ROS) production efficiency. Upon photoactivation, TPA-DHPy-Py is capable of precisely identifying cancer cells from co-culturing cancer cells and normal cells without the assistance of any extra targeting units, and in situ monitoring lipid droplets and endoplasmic reticulum alteration under ROS stress, as well as achieving fluorescent visualization of tumor in vivo with supremely high imaging contrast. Furthermore, the unprecedented performance on photodynamic cancer therapy is demonstrated by the significant inhibition of tumor growth. Therefore, the photoactivatable TPA-DHPy-Py with dual-organelle-targeted and excellent photodynamic activity associated with self-monitoring ability is highly promising for cancer theranostics in clinical trials. 相似文献
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A fully integrated dual-band RF receiver with a low-IF architecture is designed and implemented for GPS-L 1 and Compass-Bl in a 55-nm CMOS process. The receiver incorporates two independent IF channels with 2 or 4 MHz bandwidth to receive dual-band signals around 1.57 GHz respectively. By implementing a flexible frequency plan, the RF front-end and frequency synthesizer are shared for the dual-band operation to save power consumption and chip area, as well as avoiding LO crosstalk. A digital automatic gain control (AGC) loop is utilized to improve the receiver's robustness by optimizing the conversion gain of the analog-to-digital converter (ADC). While drawing about 20 mA per channel from a 1.2 V supply, this RF receiver achieves a minimum noise figure (NF) of about 1.8 dB, an image rejection (IMR) of more than 35 dB, a maximum voltage gain of about 122 dB, a gain dynamic range of 82 dB, and an maximum input-referred 1 dB compression point of about -36.5 dBm with an active die area of 1.5 × 1.4 mm2 for the whole chip. 相似文献
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不等波纹函数低通原型的理论及应用 总被引:3,自引:0,他引:3
本文提出不等波纹函数低通原型,并对其理论进行初步探讨。切比雪夫函数及最平坦型巴特活兹函数皆为其特例。文中给出不等波纹函数的几个性质,最后给出两个应用实例,消除耦合环自感部分的影响;抑制高次模的微带圆盘腔带通滤波器。 相似文献