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Photonic crystals

Runyu Zhang, Joseph Cohen, Shanhui Fan, Paul V Braun
Rhenium-Nickel (RexNi100-x) based 3D metallic inverse opals (IOs) were realized via colloidal crystal templated electrodeposition from an aqueous electrolyte. By varying the electrodeposition parameters, x could be varied from 0 to 88. Under reducing conditions, the rhenium-rich IOs were structurally stable to temperatures of at least 1000 °C for 5 h and for at least 12 h after coating with a thin layer of Al2O3. This demonstrated level of thermal stability is significantly improved compared to previously reported electrodeposited refractory inverse opals with similar characteristic dimensions...
July 27, 2017: Nanoscale
Hui Liu, Hangzhou Yang, Xueguang Qiao, Yongqiang Wang, Xiaochong Liu, Yen-Sian Lee, Kok-Sing Lim, Harith Ahmad
We have experimentally demonstrated an optical fiber Mach-Zehnder interferometer (MZI) structure formed by a few-mode photonic crystal fiber (PCF) for curvature measurement and inscribed a fiber Bragg grating (FBG) in the PCF for the purpose of simultaneously measuring temperature. The structure consists of a PCF sandwiched between two multi-mode fibers (MMFs). Bending experimental results show that the proposed sensor has a sensitivity of -1.03 nm/m(-1) at a curvature range from 10 m(-1) to 22.4 m(-1), and the curvature sensitivity of the embedded FBG was -0...
July 27, 2017: Sensors
Sun Kyung Lee, Tai Hyun Yoon, Minhaeng Cho
Quantum spectroscopy and imaging with undetected idler photons have been demonstrated by measuring one-photon interference between the corresponding entangled signal fields from two spontaneous parametric down conversion (SPDC) crystals. In this Report, we present a new quantum optical measurement scheme utilizing three SPDC crystals in a cascading arrangement; here, neither the detection of the idler photons which interact with materials of interest nor their conjugate signal photons which do not interact with the sample is required...
July 26, 2017: Scientific Reports
Ronger Lu, Jiachu Jiang, Ruizhi Zhao, Xia Feng, Xuhao Hong, Chao Zhang, Yiqiang Qin, Yongyuan Zhu
The nonreciprocal response of the SHG process in 1D periodical nonlinear photonic crystals with a defect embedded has been theoretically studied by solving the nonlinear coupled equations. The nonreciprocal response has been deduced analytically with the solution of non-reciprocity parameters obtained. The result shows that as the non-reciprocity approaches 100%, the crystal length and the input power needed increase at a logarithmic rate. Any target nonreciprocal response can be reached in this structure by adjusting the structure parameters...
July 26, 2017: Scientific Reports
Zhili Yang, Matthew Pelton, Igor Fedin, Dmitri V Talapin, Edo Waks
Colloidal semiconductor nanocrystals have emerged as promising active materials for solution-processable optoelectronic and light-emitting devices. In particular, the development of nanocrystal lasers is currently experiencing rapid progress. However, these lasers require large pump powers, and realizing an efficient low-power nanocrystal laser has remained a difficult challenge. Here, we demonstrate a nanolaser using colloidal nanocrystals that exhibits a threshold input power of less than 1 μW, a very low threshold for any laser using colloidal emitters...
July 26, 2017: Nature Communications
Yi-Han Lin, Shing-Yi Suen, Hongta Yang
With significant impacts of carbon dioxide on global climate change, carbon dioxide sensing is of great importance. However, most of the existing sensing technologies are prone to interferences from carbon monoxide, or suffer from the use of sophisticated instruments. This research reports the development of reproducible carbon dioxide sensor using roll-to-roll compatible doctor blade coated three-dimensional macroporous photonic crystals. The pores are functionalized with amine groups to allow the reaction with carbon dioxide in the presence of humidity...
July 12, 2017: Journal of Colloid and Interface Science
Lihua Ye, Yangyang Feng, Zhixiang Cheng, Chunlei Wang, Changgui Lu, Yan-Qing Lu, YiPing Cui
The coherent random laser (CRL) from dye doped polydimethylsiloxane (PDMS) has been investigated in both nanoparticles (NPs) doped thin film and pure dye thin film. Compared with the other works, the pump threshold is only 1.5 mJ/cm2 in the pure dye thin film with a low dye concentration. The micro-nano crystals of Pyrromethene 597 (PM597) dye spontaneously formed support both gain and random feedback in the bulk of the PDMS during the sample preparation. When the SiO2 NPs was doped, the pump threshold was reduced to 0...
July 24, 2017: ACS Applied Materials & Interfaces
Yongzhuo Li, Jianxing Zhang, Dandan Huang, Hao Sun, Fan Fan, Jiabin Feng, Zhen Wang, C Z Ning
Monolayer transition-metal dichalcogenides (TMDs) have the potential to become efficient optical-gain materials for low-energy-consumption nanolasers with the smallest gain media because of strong excitonic emission. However, until now TMD-based lasing has been realized only at low temperatures. Here we demonstrate for the first time a room-temperature laser operation in the infrared region from a monolayer of molybdenum ditelluride on a silicon photonic-crystal cavity. The observation is enabled by the unique combination of a TMD monolayer with an emission wavelength transparent to silicon, and a high-Q cavity of the silicon nanobeam...
July 17, 2017: Nature Nanotechnology
Alexander A Govyadinov, Andrea Konečná, Andrey Chuvilin, Saül Vélez, Irene Dolado, Alexey Y Nikitin, Sergei Lopatin, Fèlix Casanova, Luis E Hueso, Javier Aizpurua, Rainer Hillenbrand
Van der Waals materials exhibit intriguing structural, electronic, and photonic properties. Electron energy loss spectroscopy within scanning transmission electron microscopy allows for nanoscale mapping of such properties. However, its detection is typically limited to energy losses in the eV range-too large for probing low-energy excitations such as phonons or mid-infrared plasmons. Here, we adapt a conventional instrument to probe energy loss down to 100 meV, and map phononic states in hexagonal boron nitride, a representative van der Waals material...
July 21, 2017: Nature Communications
Wei Chen, Kenneth J Shea, Min Xue, Lili Qiu, Yunhe Lan, Zihui Meng
Three-dimensional photonic crystal sensors are attractive platforms for autonomous chemical sensing and colorimetric bioassays. At present, the photonic crystal sensors with inverse opal structure were extensively studied, which swells or shrinks in response to the analytes. However, the fabrication of inverse opal sensors still remains a major challenge. Herein, we propose a simple and versatile approach to fabricate 3D opal photonic sensors. This photonic crystal is fabricated via assembly of monodispersed silica particles grafted with linear polymeric ligands (SiO2@LPs)...
July 20, 2017: Analytical and Bioanalytical Chemistry
Ramachandram Badugu, Jieying Mao, Steve Blair, Douguo Zhang, Emiliano Descrovi, Angelo Angelini, Yiping Huo, Joseph R Lakowicz
The interaction of fluorophores with nearby metallic structures is now an active area of research. Dielectric photonic structures offer some advantages over plasmonic structures, namely small energy losses and less quenching. We describe a dielectric one-dimensional photonic crystal (1DPC), which supports Bloch surface waves (BSWs) from 280 to 440 nm. This BSW structure is a quartz slide coated with alternating layers of SiO2 and Si3N4. We show that this structure displays BSWs and that the near-UV fluorophore, 2-aminopurine (2-AP), on the top surface of the structure couples with the BSWs...
December 22, 2016: Journal of Physical Chemistry. C, Nanomaterials and Interfaces
Chao Liu, Zheng Wang, Erwen Li, Zexi Liang, Swapnajit Chakravarty, Xiaochuan Xu, Alan X Wang, Ray T Chen, Donglei Fan
To detect biochemicals with ultrahigh sensitivity, efficiency, reproducibility, and specificity has been the holy grail in the development of nanosensors. In this work, we report an innovative type of photonic-plasmonic hybrid Raman nanosensor integrated with electrokinetic manipulation by rational design, which offers dual mechanisms that enhance the sensitivity for molecule detection directly in solution. For the first time, we integrate large arrays of synthesized plasmonic nanocapsules with densely surface distributed silver (Ag) nanoparticles (NPs) on lithographically patterned photonic crystal slabs via electric-field assembling...
March 24, 2017: ACS Sensors
Chien-Fu Chiu, Hui-Ping Tsai, Ying-Chu Chen, Yi-Xuan He, Kun-Yi Andrew Lin, Hongta Yang
Surfactants are extensively used as detergents, dispersants, and emulsifiers. Thus, wastewater containing high-concentration surfactants discharged to the environment pose a serious threat to the ecosystem. Unfortunately, conventional detection methods for surfactants suffer from the use of sophisticated instruments and cannot perform detections for various surfactants by a single analysis. The article reports the development of simple and sensitive surfactant detection using doctor-blade-coated three-dimensional curved macroporous photonic crystals on a cylindrical rod...
July 27, 2017: ACS Applied Materials & Interfaces
L Ondič, M Varga, I Pelant, J Valenta, A Kromka, R G Elliman
Light extraction from a thin planar layer can be increased by introducing a two-dimensional periodic pattern on its surface. This structure, the so-called photonic crystal (PhC) slab, then not only enhances the extraction efficiency of light but can direct the extracted emission into desired angles. Careful design of the structures is important in order to have a spectral overlap of the emission with extraction (leaky) modes. We show that by fabricating PhC slabs with optimized dimensions from silicon nanocrystals (SiNCs) active layers, the extraction efficiency of vertical light emission from SiNCs at a particular wavelength can be enhanced ∼ 11 times compared to that of uncorrugated SiNCs-rich layer...
July 18, 2017: Scientific Reports
Simon Yves, Romain Fleury, Thomas Berthelot, Mathias Fink, Fabrice Lemoult, Geoffroy Lerosey
The exciting discovery of topological condensed matter systems has lately triggered a search for their photonic analogues, motivated by the possibility of robust backscattering-immune light transport. However, topological photonic phases have so far only been observed in photonic crystals and waveguide arrays, which are inherently physically wavelength scaled, hindering their application in compact subwavelength systems. In this letter, we tackle this problem by patterning the deep subwavelength resonant elements of metamaterials onto specific lattices, and create crystalline metamaterials that can develop complex nonlocal properties due to multiple scattering, despite their very subwavelength spatial scale that usually implies to disregard their structure...
July 18, 2017: Nature Communications
Francesco Michelotti, Riccardo Rizzo, Alberto Sinibaldi, Peter Munzert, Christoph Wächter, Norbert Danz
We report on the fabrication and physical characterization of optical biosensors implementing simultaneous label-free and fluorescence detection and taking advantage of the excitation of Bloch surface waves at a photonic crystal's truncation interface. Two types of purposely designed one-dimensional photonic crystals on molded organic substrates with micro-optics were fabricated. These crystals feature either high or low finesse of the Bloch surface wave resonances and were tested on the same optical readout system...
July 15, 2017: Optics Letters
F Köttig, F Tani, J C Travers, P St J Russell
We identify a novel regime of soliton-plasma interactions in which high-intensity ultrashort pulses of intermediate soliton order undergo coherent plasma-induced fission. Experimental results obtained in gas-filled hollow-core photonic crystal fiber are supported by rigorous numerical simulations. In the anomalous dispersion regime, the cumulative blueshift of higher-order input solitons with ionizing intensities results in pulse splitting before the ultimate self-compression point, leading to the generation of robust pulse pairs with PHz bandwidths...
June 30, 2017: Physical Review Letters
Xi-Wang Luo, Xingxiang Zhou, Jin-Shi Xu, Chuan-Feng Li, Guang-Can Guo, Chuanwei Zhang, Zheng-Wei Zhou
All-optical photonic devices are crucial for many important photonic technologies and applications, ranging from optical communication to quantum information processing. Conventional design of all-optical devices is based on photon propagation and interference in real space, which may rely on large numbers of optical elements, and the requirement of precise control makes this approach challenging. Here we propose an unconventional route for engineering all-optical devices using the photon's internal degrees of freedom, which form photonic crystals in such synthetic dimensions for photon propagation and interference...
July 14, 2017: Nature Communications
Nishan Mann, Stephen Hughes
We introduce a new coupled mode theory to model nonlinear Schrödinger equations for counterpropagating Bloch modes that include disorder-induced multiple scattering effects on nonlinear soliton propagation in photonic crystal waveguides. We also derive subunit-cell coupling coefficients and use these to introduce a generalized length scale associated with each coupling effect. In particular, we define a multiple-scattering length scale that quantifies the spatial extent of a disorder-induced cavity mode. Our numerical simulations of nonlinear pulse propagation are in excellent qualitative agreement with recent experiments and provide insight into how structural disorder inhibits soliton propagation and other nonlinear propagation effects in photonic crystal waveguides...
June 23, 2017: Physical Review Letters
Saravanan Panneerselvam, Esa Pekka Kumpula, Inari Kursula, Anja Burkhardt, Alke Meents
Cadmium ions can be effectively used to promote crystal growth and for experimental phasing. Here, the use of cadmium ions as a suitable anomalous scatterer at the standard wavelength of 1 Å is demonstrated. The structures of three different proteins were determined using cadmium single-wavelength anomalous dispersion (SAD) phasing. Owing to the strong anomalous signal, the structure of lysozyme could be automatically phased and built using a very low anomalous multiplicity (1.1) and low-completeness (77%) data set...
July 1, 2017: Acta Crystallographica. Section D, Structural Biology
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