Exceptional points of all-dielectric nanoresonators

Abstract In the recent years, all-dielectric nanophotonics has been showing promising potential for biotechnology, with important progress in the development of efficient all-optical, all-dielectric nanosensing devices overcoming the ohmic losses inherently present in their plasmonic counterparts. In the quest to achieve single molecule sensitivities, a judicious design of the optical response of the nanoantennas is required. Here, we approach this problem from the perspective of non-Hermitian physics and investigate the interaction of two finite nanorods supporting Mie resonances, with the aim of maximizing the frequency detuning induced by a perturbation of the structure. We develop a simple semi-analytical technique to efficiently investigate the coupled system, and we find that Coulomb interactions, together with mutual interference induced by breaking the dimer symmetry, can effectively bring the structure towards a non-Hermitian singularity, an exceptional point, that can potentially increase the sensitivity. The results of this work are expected to lead to novel developments in all-optical single molecule detection, and merge for the first time all-dielectric nanophotonics with exceptional point physics.

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Probing molecular properties and the role of the environment at the single-molecule level

Pure and Applied Chemistry ◽

10.1351/pac200678122261 ◽

2006 ◽

Vol 78 (12) ◽

pp. 2261-2266 ◽

Cited By ~ 3

Author(s):

J. Hofkens ◽

T. D. M. Bell ◽

A. Stefan ◽

E. Fron ◽

K. Müllen ◽

...

Keyword(s):

Single Molecule ◽

Conformational Changes ◽

Local Environment ◽

Coupled System ◽

Strongly Coupled ◽

Single Molecule Level ◽

Weakly Coupled ◽

Weakly Coupled System ◽

Donor Acceptor ◽

First Time

Evidence for intramolecular photoinduced electron transfer (ET) in synthetic systems consisting of a triphenylamine-perylenediimide donor-acceptor dendrimer or a triphenylamine-peryleneimide dendrimer at the ensemble and single-molecule (SM) level is presented. Moreover, for the first time a direct observation of the forward as well as the backward ET step is made in a single emitting entity. Fluctuations in the values of the rate constants for forward and backward ET were observed, induced by the local environment as well as by conformational changes of the dendrimer itself. The results obtained in a weakly coupled system can also be extended to a strongly coupled donor-acceptor system based on peryleneimide and penta-phenylene.

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Recent developments in low-voltage SEM of polymers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100150162 ◽

1993 ◽

Vol 51 ◽

pp. 866-867

Author(s):

S.J. Krause ◽

W.W. Adams

Keyword(s):

Low Voltage ◽

Chromatic Aberration ◽

Thermal Electron ◽

Analytical Technique ◽

Recent Developments ◽

Beam Currents ◽

New Generation ◽

First Time ◽

Voltage Scanning ◽

Beam Damage

Over the past decade low voltage scanning electron microscopy (LVSEM) of polymers has evolved from an interesting curiosity to a powerful analytical technique. This development has been driven by improved instrumentation and in particular, reliable field emission gun (FEG) SEMs. The usefulness of LVSEM has also grown because of an improved theoretical and experimental understanding of sample-beam interactions and by advances in sample preparation and operating techniques. This paper will review progress in polymer LVSEM and present recent results and developments in the field.In the early 1980s a new generation of SEMs produced beam currents that were sufficient to allow imaging at low voltages from 5keV to 0.5 keV. Thus, for the first time, it became possible to routinely image uncoated polymers at voltages below their negative charging threshold, the "second crossover", E2 (Fig. 1). LVSEM also improved contrast and reduced beam damage in sputter metal coated polymers. Unfortunately, resolution was limited to a few tenths of a micron due to the low brightness and chromatic aberration of thermal electron emission sources.

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Frequency Encoded All Optical Tri-state Logic Gates NOT and NAND Using Semiconductor Optical Amplifier Based Interferometric Switches

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681209666190620110027 ◽

2020 ◽

Vol 10 (4) ◽

pp. 369-380

Author(s):

K. Maji ◽

K. Mukherjee ◽

A. Raja

Keyword(s):

Semiconductor Optical Amplifier ◽

Extinction Ratio ◽

Optical Power ◽

Logic Gates ◽

Optical Amplifier ◽

All Optical ◽

State Frequency ◽

Spontaneous Noise ◽

First Time ◽

Practical Feasibility

All optical tri-state frequency encoded logic gates NOT and NAND are proposed and numerically investigated using TOAD based interferometric switch for the first time to the best of our knowledge. The optical power spectrum, extinction ratio, contrast ration, and amplified spontaneous noise are calculated to analyze and confirm practical feasibility of the gates. The proposed device works for low switching energy and has high contrast and extinction ratio as indicated in this work.

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Survey of the Bradysia odoriphaga Transcriptome Using PacBio Single-Molecule Long-Read Sequencing

Genes ◽

10.3390/genes10060481 ◽

2019 ◽

Vol 10 (6) ◽

pp. 481 ◽

Cited By ~ 1

Author(s):

Chen ◽

Lin ◽

Xie ◽

Zhong ◽

Zhang ◽

...

Keyword(s):

Insecticide Resistance ◽

Single Molecule ◽

Functional Categories ◽

Genetic Studies ◽

Sequencing Technologies ◽

Clusters Of Orthologous Groups ◽

Long Read ◽

Main Gene ◽

First Time ◽

Main Factor

The damage caused by Bradysia odoriphaga is the main factor threatening the production of vegetables in the Liliaceae family. However, few genetic studies of B. odoriphaga have been conducted because of a lack of genomic resources. Many long-read sequencing technologies have been developed in the last decade; therefore, in this study, the transcriptome including all development stages of B. odoriphaga was sequenced for the first time by Pacific single-molecule long-read sequencing. Here, 39,129 isoforms were generated, and 35,645 were found to have annotation results when checked against sequences available in different databases. Overall, 18,473 isoforms were distributed in 25 various Clusters of Orthologous Groups, and 11,880 isoforms were categorized into 60 functional groups that belonged to the three main Gene Ontology classifications. Moreover, 30,610 isoforms were assigned into 44 functional categories belonging to six main Kyoto Encyclopedia of Genes and Genomes functional categories. Coding DNA sequence (CDS) prediction showed that 36,419 out of 39,129 isoforms were predicted to have CDS, and 4319 simple sequence repeats were detected in total. Finally, 266 insecticide resistance and metabolism-related isoforms were identified as candidate genes for further investigation of insecticide resistance and metabolism in B. odoriphaga.

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A NEW LAYOUT DESIGN SYSTEM FOR MULTICHIP MODULES

International Journal of High Speed Electronics and Systems ◽

10.1142/s0129156495000171 ◽

1995 ◽

Vol 06 (03) ◽

pp. 509-538 ◽

Cited By ~ 1

Author(s):

BERNHARD M. RIESS ◽

ANDREAS A. SCHOENE

Keyword(s):

Efficient Algorithm ◽

State Of The Art ◽

Layout Design ◽

The State ◽

Design System ◽

Multichip Modules ◽

Analytical Technique ◽

Cut Method ◽

First Time ◽

Three Components

A new layout design system for multichip modules (MCMs) consisting of three components is described. It includes a k-way partitioning approach, an algorithm for pin assignment, and a placement package. For partitioning, we propose an analytical technique combined with a problem-specific multi-way ratio cut method. This method considers fixed module-level pad positions and assigns the cells to regularly arranged chips on the MCM substrate. In the subsequent pin assignment step the chip-level pads resulting from cut nets are positioned on the chip borders. Pin assignment is performed by an efficient algorithm, which profits from the cell coordinates generated by the analytical technique. Global and final placement for each chip is computed by the state-of-the-art placement tools GORDIANL and DOMINO. For the first time, results for MCM layout designs of benchmark circuits with up to 100,000 cells are presented. They show a small number of required chip-level pads, which is the most restricted resource in MCM design, and short total wire lengths.

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Label-free single-molecule all-optical sensor

10.1117/12.761007 ◽

2008 ◽

Author(s):

Andrea M. Armani ◽

Scott E. Fraser ◽

Richard C. Flagan

Keyword(s):

Single Molecule ◽

Optical Sensor ◽

Label Free ◽

All Optical

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All-optical dynamic tuning of local excitonic emission of monolayer MoS2 by integration with Ge2Sb2Te5

Nanophotonics ◽

10.1515/nanoph-2019-0366 ◽

2020 ◽

Vol 9 (8) ◽

pp. 2351-2359

Author(s):

Hao Ouyang ◽

Haitao Chen ◽

Yuxiang Tang ◽

Jun Zhang ◽

Chenxi Zhang ◽

...

Keyword(s):

Thin Film ◽

Phase Change ◽

Optical Networks ◽

Dominant Role ◽

Laser Pulses ◽

Coulomb Interactions ◽

Optical Modulators ◽

Dynamic Tuning ◽

All Optical ◽

Excitonic Emission

AbstractStrong quantum confinement and coulomb interactions induce tightly bound quasiparticles such as excitons and trions in an atomically thin layer of transitional metal dichalcogenides (TMDs), which play a dominant role in determining their intriguing optoelectronic properties. Thus, controlling the excitonic properties is essential for the applications of TMD-based devices. Here, we demonstrate the all-optical tuning of the local excitonic emission from a monolayer MoS2 hybridized with phase-change material Ge2Sb2Te5 (GST) thin film. By applying pulsed laser with different power on the MoS2/GST heterostructure, the peak energies of the excitonic emission of MoS2 can be tuned up to 40 meV, and the exciton/trion intensity ratio can be tuned by at least one order of magnitude. Raman spectra and transient pump-probe measurements show that the tunability originated from the laser-induced phase change of the GST thin film with charge transferring from GST to the monolayer MoS2. The dynamic tuning of the excitonic emission was all done with localized laser pulses and could be scaled readily, which pave a new way of controlling the excitonic emission in TMDs. Our findings could be potentially used as all-optical modulators or switches in future optical networks.

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PacBio Single-Molecule Long-Read Sequencing Reveals Genes Tolerating Manganese Stress in Schima superba Saplings

Frontiers in Genetics ◽

10.3389/fgene.2021.635043 ◽

2021 ◽

Vol 12 ◽

Author(s):

Fiza Liaquat ◽

Muhammad Farooq Hussain Munis ◽

Samiah Arif ◽

Urooj Haroon ◽

Jianxin Shi ◽

...

Keyword(s):

Single Molecule ◽

Gene Annotation ◽

Treated Group ◽

Full Length ◽

Open Reading Frames ◽

Interacting Protein ◽

Schima Superba ◽

Long Read ◽

First Time ◽

Potential Tool

Schima superba (Theaceae) is a subtropical evergreen tree and is used widely for forest firebreaks and gardening. It is a plant that tolerates salt and typically accumulates elevated amounts of manganese in the leaves. With large ecological amplitude, this tree species grows quickly. Due to its substantial biomass, it has a great potential for soil remediation. To evaluate the thorough framework of the mRNA, we employed PacBio sequencing technology for the first time to generate S. Superba transcriptome. In this analysis, overall, 511,759 full length non-chimeric reads were acquired, and 163,834 high-quality full-length reads were obtained. Overall, 93,362 open reading frames were obtained, of which 78,255 were complete. In gene annotation analyses, the Kyoto Encyclopedia of Genes and Genomes (KEGG), Clusters of Orthologous Genes (COG), Gene Ontology (GO), and Non-Redundant (Nr) databases were allocated 91,082, 71,839, 38,914, and 38,376 transcripts, respectively. To identify long non-coding RNAs (lncRNAs), we utilized four computational methods associated with protein families (Pfam), Cooperative Data Classification (CPC), Coding Assessing Potential Tool (CPAT), and Coding Non-Coding Index (CNCI) databases and observed 8,551, 9,174, 20,720, and 18,669 lncRNAs, respectively. Moreover, nine genes were randomly selected for the expression analysis, which showed the highest expression of Gene 6 (Na_Ca_ex gene), and CAX (CAX-interacting protein 4) was higher in manganese (Mn)-treated group. This work provided significant number of full-length transcripts and refined the annotation of the reference genome, which will ease advanced genetic analyses of S. superba.

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Particle precipitations during NEIAL events: simultaneous ground based observations at Svalbard

Annales Geophysicae ◽

10.5194/angeo-25-1323-2007 ◽

2007 ◽

Vol 25 (6) ◽

pp. 1323-1336 ◽

Cited By ~ 3

Author(s):

J. Lunde ◽

B. Gustavsson ◽

U. P. Løvhaug ◽

D. A. Lorentzen ◽

Y. Ogawa

Keyword(s):

Minimum Energy ◽

Soft Particle ◽

Particle Precipitation ◽

Characteristic Energy ◽

Incoherent Scatter ◽

Large Numbers ◽

All Optical ◽

Ion Acoustic ◽

Scatter Spectrum ◽

First Time

Abstract. In this paper we present Naturally Enhanced Ion Acoustic Lines (NEIALs) observed with the EISCAT Svalbard Radar (ESR). For the first time, long sequences of NEIALs are recorded, with more than 50 events within an hour, ranging from 6.4 to 140 s in duration. The events took place from ~08:45 to 10:00 UT, 22 January 2004. We combine ESR data with observations of optical aurora by a meridian scanning photometer at wavelengths 557.7, 630.0, 427.8, and 844.6 nm, as well as records from a magnetometer and an imaging riometer. The large numbers of observed NEIALs together with these additional observations, enable us to characterise the particle precipitation during the NEIAL events. We find that the intensities in all optical lines studied must be above a certain level for the NEIALs to appear. We also find that the soft particle precipitation is associated with the down-shifted shoulder in the incoherent scatter spectrum, and that harder precipitation may play a role in the enhancement of the up-shifted shoulder. The minimum energy flux during NEIAL events found in this study was ~3.5 mW/m2 and minimum characteristic energy around 50 eV.

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GC-MS Chemical Characterization of Main Components of Smilax Domingensis Wild. in Cuba

Journal of Agricultural Studies ◽

10.5296/jas.v6i2.13099 ◽

2018 ◽

Vol 5 (4) ◽

pp. 79 ◽

Cited By ~ 1

Author(s):

Pilar A. Soledispa ◽

José González ◽

Armando Cuéllar ◽

Julio Pérez ◽

Max Monan

Keyword(s):

Mass Spectra ◽

Chemical Constituents ◽

Chemical Characterization ◽

Ethanolic Extract ◽

Chemical Compounds ◽

Chemical Components ◽

Analytical Technique ◽

Main Components ◽

First Time

A preliminary chemical characterization of main components of ethanolic extract with dried rhizomes of Smilax domingensis Wid. that grow in Cuba was done using a GCMS-QP2010 Ultra Shimadzu and the mass spectra of the compounds found in the extract was matched with the National Institute of Standards and Technology (NIST) library. After sample derivatization 125 chemical compounds were registered by the equipment and from them, 35 different chemical components were characterized and reported for the first time from this part of the plant in our country. The results demonstrate the developed method could be employed as a rapid and versatile analytical technique for identification of chemical constituents and quality control of Smilax domingensis.

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