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Semiconductor plasmonic

Nidhi Pandit, Rahul Kumar Jaiswal, Nagendra Prasad Pathak
In this Letter, we report the design, analysis, and characterization of first- and second-order plasmonic metamaterial-based multi-mode filtering structures. Further, electronic adaptivity in filter transfer functions is introduced and characterized. First, the basic operating principle of the engineered multi-mode resonator-based bandpass filter is presented. Then the concept is extended by introducing electronic (dynamic) tuning of the bandwidth using semiconductor varactor diodes. Afterwards, to enhance the selectivity and out-of-band filtering response, second-order multi-mode designs are realized...
February 15, 2019: Optics Letters
Pawan Kumar, Ehsan Vahidzadeh, Ujwal Kumar Thakur, Piyush Kar, Kazi Mohammad Alam, Ankur Goswami, Najia Mahdi, Kai Cui, Guy M Bernard, Vladimir K Michaelis, Karthik Shankar
Modification of carbon nitride based polymeric 2D materials for tailoring their optical, electronic and chemical properties for various applications has gained significant interest. The present report demonstrates the synthesis of a novel modified carbon nitride framework with a remarkable 3:5 C:N stoichiometry (C3N5) and an electronic bandgap of 1.76 eV, by thermal deammoniation of melem hydrazine precursor. Characterization revealed that in C3N5 polymer, two s-heptazine units are bridged together with azo linkage, which constitutes an entirely new and different bonding fashion from g-C3N4 where three heptazine units are linked together with tertiary nitrogen...
February 14, 2019: Journal of the American Chemical Society
Songling Xing, Luchan Lin, Jinpeng Huo, Guisheng Zou, Xing Sheng, Lei Liu, Y Norman Zhou
In this work, plasmon induced heterointerface thinning for Schottky barrier modification of core/shell SiC/SiO2 nanowire is conducted by femtosecond (fs) laser irradiation. The incident energy of polarized fs laser (50 fs, 800 nm) is confined in SiO2 shell of the nanowire due to strong plasmonic localization in the region of electrode-nanowire junction. With intense non-linear absorption in SiO2 , the thickness of SiO2 layer can be thinned in a controllable way. The tuning of SiO2 barrier layer allows to promote the electron transportation at the electrode-nanowire interface...
February 13, 2019: ACS Applied Materials & Interfaces
Amin Azizi, Gabriel Antonius, Emma Regan, Rahmatollah Eskandari, Salman Kahn, Feng Wang, Steven G Louie, Alex Zettl
Alloying two-dimensional (2D) semiconductors provides a powerful method to tune their physical properties, especially those relevant to optoelectronic applications. However, as the crystal structure becomes more complex, it becomes increasingly difficult to accurately correlate response characteristics to detailed atomic structure. We investigate, via annular dark-field scanning transmission electron microscopy, electron energy loss spectroscopy, and second harmonic generation, the layered III-VI alloy GaSe0...
February 12, 2019: Nano Letters
Arkadiusz Ciesielski, Lukasz Skowronski, Marek Trzcinski, Ewa Górecka, Wojciech Pacuski, Tomasz Szoplik
Noble metal nanolayers on flat substrates are often deposited with the use of semiconductor interlayers, which may strongly interact with the noble metal overlayer. We investigated the crystallinity, atomic concentration profile and optical parameters of ≈35 nm-thick silver and gold layers deposited on glass substrates with 2 nm-thick tellurium or selenium interlayers. Our study, based on X-ray reflectometry (XRR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and ellipsometric measurements, showed that using either of these interlayers introduces strain in nanocrystals of both plasmonic films...
2019: Beilstein Journal of Nanotechnology
Chuang Han, Shao-Hai Li, Zi-Rong Tang, Yi-Jun Xu
Considerable effort has been devoted to manipulating the optical absorption of metal nanostructures for diverse applications. However, it still remains a challenge to develop a general and flexible method to promote broadband absorption of metal nanostructures without changing their size and shape. Here, we report a new strategy of hybridizing two conceptually different optical models to realize broadband absorption enhancement of metal nanoparticles (NPs), which is enabled by constructing a core-shell heterostructure, consisting of a spherical dielectric core covered by a metal NPs interlayer and tunable semiconductor shell...
December 28, 2018: Chemical Science
Juan Tang, Pengyuan Xiong, Yu Cheng, Ya Chen, Siwen Peng, Zhi-Qiang Zhu
A well-defined Ag@AgCl nanocubes loaded on the reduced graphene oxide plasmonic heterostructure (Ag@AgCl/RGO) was facilely prepared by sacrificial salt-crystal-template process and ethylene glycol-assisted reduction. The Ag@AgCl/RGO heterostructure shows superior photocurrent response and stability under the visible light irradiation. The enhanced performance mainly attributes to the plasmon resonance effect of AgNPs by improving the absorbance and transfer of photogenerated electrons. Significantly, we observed that the photocurrent could be dramatically decreased with the introduction of H2 O2 and experimental results demonstrated the etching effect of H2 O2 to AgNPs should be responsible for this phenomenon...
January 15, 2019: Biosensors & Bioelectronics
Ning Ma, Xin-Yuan Zhang, Wenyue Fan, Bingbing Han, Sila Jin, Yeonju Park, Lei Chen, Yongjun Zhang, Yang Liu, Jinghai Yang, Young Mee Jung
In this work, we introduced an ordered metal-semiconductor molecular system and studied the resulting surface-enhanced Raman scattering (SERS) effect. Ag-FeS nanocaps with sputtered films of different thicknesses were obtained by changing the sputtering power of FeS while the sputtering power of Ag and the deposition time remained constant. When metallic Ag and the semiconductor FeS are cosputtered, the Ag film separates into Ag islands partially covered by FeS and strong coupling occurs among the Ag islands isolated by FeS, which contributes to the SERS phenomenon...
February 2, 2019: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Jun Liu, Zhaohui Wu, Quanguo He, Qingyong Tian, Wei Wu, Xiangheng Xiao, Changzhong Jiang
For an economical use of solar energy, photocatalysts that are sufficiently efficient, stable, and capable of harvesting light are required. Composite heterostructures composed of noble metals and semiconductors exhibited the excellent in catalytic application. Here, 1D Ag/Au/AgCl hollow heterostructures are synthesized by galvanic replacement reaction (GRR) from Ag nanowires (NWs). The catalytic properties of these as-obtained Ag/Au/AgCl hollow heterostructures with different ratios are investigated by reducing 4-nitrophenol (Nip) into 4-aminophenol (Amp) in the presence of NaBH4 , and the influence of AgCl semiconductor to the catalytic performances of Ag/Au bimetals is also investigated...
January 25, 2019: Nanoscale Research Letters
Xiangyu Hou, Xiaoguang Luo, Xingce Fan, Zhaohui Peng, Teng Qiu
Transition metal oxide semiconductors have been explored in surface-enhanced Raman scattering (SERS) active substrates, yet their detection sensitivity and enhancement effects are inferior. What's more, the reported fabrication technique ignored the effects of the electromagnetic mechanisms and was far from satisfactory for practical applications. Herein, we report on a convenient nanotechnique to fabricate large-area hexagon plum-blossom-like WO3-x nanoarrays based on aluminum nanobowl array substrates. Localized surface plasmon resonance can be increased via adjusting the time of tungsten magnetron sputtering with H2 annealing treatment...
January 18, 2019: Physical Chemistry Chemical Physics: PCCP
Young-Youb Kim, Yongbin Bang, Ah-Hyoung Lee, Yoon-Kyu Song
Here we explore the extended utility of two important functional biomolecules, DNA and protein, by hybridizing them through avidin-biotin conjugation. We report a simple yet scalable technique of successive magnetic separations to synthesize traptavidin-DNA conjugates with four distinct DNA binding sites, which can be used as a supramolecular building block for programmable assembly of nanostructures. Using this nano-assembly platform, we fabricate several different plasmonic nanostructures with various metallic as well as semiconductor nanoparticles in predetermined ways...
January 17, 2019: ACS Nano
Y Ye, F Liu, K Cui, X Feng, W Zhang, Y Huang
Surface plasmon amplification by stimulated emission of radiation (SPASER) is discovered and used for realizing lasers at nanometer scale. The conventional gain media that are applied in SPASER are solid materials, such as organic dye or semiconductor, which limits the frequency range of SPASER. The free electrons could be considered as a kind of gain medium for emitting radiation. Here, we investigate theoretically the SPASER, which is excited by free electrons. We also demonstrate the tunable, deep-ultraviolet, and ultracompact laser numerically by having free electrons interact with surface plasmon polariton mode supported on metal surface...
November 26, 2018: Optics Express
Michael H Huang
Recent observations of facet-dependent electrical conductivity and photocatalytic activity of various semiconductor crystals are presented. Then, the discovery of facet-dependent surface plasmon resonance absorption of metal-Cu2 O core-shell nanocrystals with tunable sizes and shapes is discussed. The Cu2 O shells also exhibit a facet-specific optical absorption feature. The facet-dependent electrical conductivity, photocatalytic activity, and optical properties are related phenomena, resulting from the presence of an ultrathin surface layer with different band structures and thus varying degrees of band bending for the {100}, {110}, and {111} faces of Cu2 O to absorb light of somewhat different wavelengths...
January 16, 2019: Small
Andrey A Vyshnevyy, Dmitry Yu Fedyanin
The recently developed plasmonic and photonic metal-semiconductor nanolasers feature unique properties, such as ultra-small mode volume and footprint, high Purcell factor, and ultra-fast modulation. However, it is often difficult to recognize when the transition to lasing occurs, while the most important feature of laser radiation, i.e., coherence, is available only above the lasing threshold. Here we systematically study the second-order coherence properties of metal-semiconductor nanolasers at both low- and high-pump rates...
December 10, 2018: Optics Express
Xiao Wu, Xiao-Fang Jiang, Xiaowen Hu, Ding-Feng Zhang, Shuang Li, Xiang Yao, Wangwang Liu, Hin-Lap Yip, Zhilie Tang, Qing-Hua Xu
Solution-processed organo-lead halide perovskites have emerged as promising optical gain media for tunable coherent light sources. The lasing performance is generally determined by the as-synthesized crystal quality. Noble metal nanostructures have been widely utilized to enhance optical responses due to their unique property of localized surface plasmon resonance. Herein, we report a simple method to enhance the near-infrared amplified spontaneous emission (ASE) performance of MAPbI3 polycrystalline films by solution-processing a PMMA spacer layer and an Au NR-doped PMMA top layer on perovskite thin films...
January 15, 2019: Nanoscale
Eric Ashalley, Karol Gryczynski, Zhiming Wang, Gregory Salamo, Arup Neogi
A hot-electron-enabled route to controlling light with dissipative loss compensation in semiconductor quantum light emitters has been realized for tunable quantum optoelectronic devices via a two-species plasmon system. The dual species nano-plasmonic system is achieved by combining UV-plasmonic gallium metal nanoparticles (GaNPs) with visible-plasmonic gold metal nanoparticles (AuNPs) on a near-infrared two-dimensional GaAs/AlGaAs quantum well emitter. It has been demonstrated that while hot carrier-powered charge-transfer processes can result in semiconductor doping and increased optical absorption, photo-generated carrier density in the quantum well can also be modulated by off-resonant plasmonic interaction without thermal dissipation...
January 11, 2019: Nanoscale
Hao Wang, Jinxiu Wen, Weiliang Wang, Ningsheng Xu, Pu Liu, Jiahao Yan, Huanjun Chen, Shaozhi Deng
Light-matter resonance coupling is a long-studied topic for both fundamental research and photonic and optoelectronic applications. Here we investigated the resonance coupling between the magnetic dipole mode of a dielectric nanosphere and 2D excitons in a monolayer semiconductor. By coating an individual silicon nanosphere with a monolayer of WS2, we theoretically demonstrated that, because of the strong energy transfer between the magnetic dipole mode of the nanosphere and the A-exciton in WS2, resonance coupling evidenced by anticrossing behavior in the scattering energy diagram was observed, with a mode splitting of 43 meV...
January 10, 2019: ACS Nano
Keng-Te Lin, Chih-Jie Chan, Yu-Sheng Lai, Lung-Tai Shiu, Ching-Che Lin, Hsuen-Li Chen
Although the use of plasmonic nanostructures for photodetection below the band gap energy of the semiconductor has been intensively investigated recently, efficiencies of such hot electron-based devices have, unfortunately, remained low because of the inevitable energy loss of the hot electrons as they move and transfer in active antennas based on metallic nanostructures. In this work, we demonstrate the concept of high-refractive-index material-embedded trench-like (ETL) active antennas that could be used to achieve almost 100% absorbance within the ultrashallow region (approximately 10 nm) beneath the metal-semiconductor interface, which is a much smaller distance compared with the hot electrons' mean free path in the noble metal layer...
January 9, 2019: ACS Applied Materials & Interfaces
Victor Krivenkov, Simon Goncharov, Pavel Samokhvalov, Ana Sánchez-Iglesias, Marek Grzelczak, Igor Nabiev, Yury P Rakovich
Semiconductor quantum dots (QDs) are known for their ability to multiphoton emission caused by recombination of biexcitons (BX). However, the quantum yield (QY) of BX emission is low due to the fast Auger process. Plasmonic nanoparticles (PNPs) provide an attractive opportunity to accelerate the BX radiative recombination. Here, we demonstrate the PNPs-induced distance-controlled enhancement of the BX emission of single QDs. Studying the same single QD before and after its integration with the PNPs, we observed the plasmon-mediated increase in the QY of BX emission...
January 7, 2019: Journal of Physical Chemistry Letters
Fengcai Lei, Huimin Liu, Jing Yu, Zhao Tang, Junfeng Xie, Pin Hao, Guanwei Cui, Bo Tang
An ideal interface model combining a hematite nanoplate-based photoanode with Au nanoparticles (NPs) is proposed for elucidating the specific role of Au NPs in photoelectrochemical performances. The theoretical and experimental results reveal that Au/Fe2O3 nanoplates can lead to an enhanced localized electric field at the metal-semiconductor interface upon the formation of surface plasmon resonance and hot electrons, which can be injected into the conduction band of the semiconductor, thus improving the efficiency of the generation and separation of electron-hole pairs...
January 4, 2019: Physical Chemistry Chemical Physics: PCCP
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