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1.
Nanoscale Horiz ; 5(4): 705-713, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32226968

RESUMO

Two-dimensional (2D) metal-free sheets with atomic thickness have been highly considered as promising candidates for fluorescent probes, due to their intriguing characteristics. In this work, 2D ultrathin boron nanosheets (B NSs) with a surface defect nanolayer can be effectively prepared by modified liquid phase exfoliation. The as-prepared ultrathin B NSs show blue fluorescence characteristics even with a quantum yield efficiency of up to 10.6%. Such luminescent behavior originates from the quantum confinement effect and the existence of a surface defect layer. In light of the advantages of being environmentally friendly, having high photostability and good biocompatibility, for the first time we have shown that ultrathin B NSs can be used as an emerging fluorescent probe for application in cellular bioimaging. It is believed that this work will open new avenues for ultrathin B NSs in biomedical fields, and it will also inspire the development of other elemental 2D nanomaterials.

2.
Cell Death Dis ; 11(2): 140, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32080168

RESUMO

Cardiac hypertrophy (CH) is an independent risk factor for many cardiovascular diseases, and is one of the primary causes of morbidity and mortality in elderly people. Pathological CH involves excessive protein synthesis, increased cardiomyocyte size, and ultimately the development of heart failure. Myotubularin-related protein 14 (MTMR14) is a member of the myotubularin (MTM)-related protein family, which is involved in apoptosis, aging, inflammation, and autophagy. However, its exact function in CH is still unclear. Herein, we investigated the roles of MTMR14 in CH. We show that MTMR14 expression was increased in hypertrophic mouse hearts. Mice deficient in heart MTMR14 exhibited an aggravated aortic-banding (AB)-induced CH phenotype. In contrast, MTMR14 overexpression prevented pressure overload-induced hypertrophy. At the molecular level, prevention of CH in the absence of MTMR14 involved elevations in Akt pathway components, which are key elements that regulate apoptosis and cell proliferation. These results demonstrate that MTMR14 is a new molecular target for the treatment of CH.

3.
Nanoscale Horiz ; 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32105281

RESUMO

Mixed-dimensional binary heterostructures, especially 0D/2D heterostructures, have attracted significant attention due to their unique physical properties. In this contribution, 0D bismuth quantum dots (Bi QDs, VA) are immobilized onto 2D Te nanosheets (Te NSs, VIA) to prepare Bi QDs/Te NSs binary heterostructures (Bi/Te) through a facile and cost-effective hydrothermal method. The results from both experiments and density functional theory (DFT) calculations demonstrate the enhanced photo-response behaviors of Bi/Te-based photoelectrochemical (PEC)-type photodetectors (PDs). The as-prepared PDs exhibit a high photocurrent of 18.21 µA cm-2, significantly higher than those of previously reported pristine Bi QD and Te NS-based PDs. The PDs are further demonstrated to have excellent self-power capability and long-term stability over 30 days. Additionally, the obtained 786 fs pulse output signal in the telecommunications band reveals the great potential of Bi/Te for ultrafast photonic devices. It is believed that such VA/VIA binary heterostructures provide opportunities for developing multifunctional optoelectronic devices for nano-science applications.

4.
Nanoscale ; 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32080700

RESUMO

Owing to their intriguing characteristics, the ongoing pursuit of emerging mono-elemental two-dimensional (2D) nanosheets beyond graphene is an exciting research area for next-generation applications. Herein, we demonstrate that highly crystalline 2D boron (B) nanosheets can be efficiently synthesized by employing a modified liquid phase exfoliation method. Moreover, carrier dynamics has been systematically investigated by using femtosecond time-resolved transient absorption spectroscopy, demonstrating an ultrafast recovery speed during carrier transfer. Based on these results, the optoelectronic performance of the as-synthesized 2D B nanosheets has been investigated by applying them in photoelectrochemical (PEC)-type and field effect transistor (FET)-type photodetectors. The experimental results revealed that the as-fabricated PEC device not only exhibited a favourable self-powered capability, but also a high photoresponsivity of 2.9-91.7 µA W-1 in the UV region. Besides, the FET device also exhibited a tunable photoresponsivity in the range of 174-281.3 µA W-1 under the irradiation of excited light at 405 nm. We strongly believe that the current work shall pave the path for successful utilization of 2D B nanosheets in electronic and optoelectronic devices. Moreover, the proposed method can be utilized to explore other mono-elemental 2D nanomaterials.

5.
Carbohydr Polym ; 232: 115448, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31952577

RESUMO

Genetic modification of plant cell walls is an effective approach to reduce lignocellulose recalcitrance in biofuel production, but it may affect plant stress response. Hence, it remains a challenge to reduce biomass recalcitrance and simultaneously enhance stress resistance. In this study, the OsSUS3-transgenic plants exhibited increased cell wall polysaccharides deposition and reduced cellulose crystallinity and xylose/arabinose proportion of hemicellulose, resulting in largely enhanced biomass saccharification and bioethanol production. Additionally, strengthening of the cell wall also contributed to plant biotic resistance. Notably, the transgenic plants increased stress-induced callose accumulation, and promoted the activation of innate immunity, leading to greatly improved multiple resistances to the most destructive diseases and a major pest. Hence, this study demonstrates a significant improvement both in bioethanol production and biotic stress resistance by regulating dynamic carbon partitioning for cellulose and callose biosynthesis in OsSUS3-transgenic plants. Meanwhile, it also provides a potential strategy for plant cell wall modification.

6.
J Cell Physiol ; 235(3): 2149-2160, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31389030

RESUMO

miR-222 participates in many cardiovascular diseases, but its effect on cardiac remodeling induced by diabetes is unclear. This study evaluated the functional role of miR-222 in cardiac fibrosis in diabetic mice. Streptozotocin (STZ) was used to establish a type 1 diabetic mouse model. After 10 weeks of STZ injection, mice were intravenously injected with Ad-miR-222 to induce the overexpression of miR-222. miR-222 overexpression reduced cardiac fibrosis and improved cardiac function in diabetic mice. Mechanistically, miR-222 inhibited the endothelium to mesenchymal transition (EndMT) in diabetic mouse hearts. Mouse heart fibroblasts and endothelial cells were isolated and cultured with high glucose (HG). An miR-222 mimic did not affect HG-induced fibroblast activation and function but did suppress the HG-induced EndMT process. The antagonism of miR-222 by antagomir inhibited HG-induced EndMT. miR-222 regulated the promoter region of ß-catenin, thus negatively regulating the Wnt/ß-catenin pathway, which was confirmed by ß-catenin siRNA. Taken together, our results indicated that miR-222 inhibited cardiac fibrosis in diabetic mice via negatively regulating Wnt/ß-catenin-mediated EndMT.

7.
Int J Biol Sci ; 15(12): 2615-2626, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31754334

RESUMO

Background/Aims: Vascular smooth muscle cell (VSMC) hyperplasia plays important roles in the pathogenesis of many vascular diseases, such as atherosclerosis and restenosis. Many microRNAs (miRs) have recently been reported to regulate the proliferation and migration of VSMC. In the current study, we aimed to explore the function of miR-93 in VSMCs and its molecular mechanism. Methods: First, qRT-PCR and immunofluorescence assays were performed to determine miR-93 expression in rat VSMCs following carotid artery injury in vivo and platelet-derived growth factor-BB (PDGF-BB) stimulation in vitro. Next, the biological role of miR-93 in rat VSMC proliferation and migration was examined in vivo and vitro. EdU incorporation assay and MTT assay for measuring cell proliferation, Transwell cell invasion assay and Cell scratch wound assay for measuring cell migration. Then, the targets of miR-93 were identified. Finally, the expression levels of proteins in the Raf-ERK1/2 pathway were measured by western blot. Results: MiR-93 was upregulated in rat VSMCs following carotid artery injury in vivo. Similar results were observed in ex vivo cultured VSMCs after PDGF-BB treatment. MiR-93 inhibition suppressed neointimal formation after carotid artery injury. Moreover, our results demonstrated that a miR-93 inhibitor suppressed the PDGF-BB induced proliferation and migration of in VSMC. This inhibitor also decreased the expression levels of MMP2 and cyclin D1. Mechanistically, we discovered that mitofusin 2(Mfn2) is a direct target of miR-93. Furthermore, an analysis of the signaling events revealed that miR-93-mediated VSMC proliferation and migration occurred via the Raf-ERK1/2 pathway. Conclusions: Our findings suggest that miR-93 promotes VSMCs proliferation and migration by targeting Mfn2. MiR-93 may be a new target for treating in-stent restenosis.

8.
Small ; 15(47): e1903233, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31609534

RESUMO

Van der Waals (vdW)-integrated heterojunctions have been widely investigated in optoelectronics due to their superior photoelectric conversion capability. In this work, 0D bismuth quantum dots (Bi QDs)-decorated 1D tellurium nanotubes (Te NTs) vdW heterojunctions (Te@Bi vdWHs) are constructed by a facile bottom-up assembly process. Transient absorption spectroscopy suggests that Te@Bi vdWH is a promising candidate for new-generation optoelectronic devices with fast response properties. The subsequent experiments and density functional theory calculations demonstrate the vdW interaction between Te NTs and Bi QDs, as well as the enhanced optoelectronic characteristics owing to the plasma effects at the interface between Te NTs and Bi QDs. Moreover, Te@Bi vdWHs-based photodetectors show significantly improved photoresponse behavior in the ultraviolet region compared to pristine Te NTs or Bi QDs-based photodetectors. The proposed integration of vdWHs is expected to pave the way for constructing new nanoscale heterodevices.

9.
Plant Mol Biol ; 101(4-5): 389-401, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31432304

RESUMO

KEY MESSAGE: Overexpression of cotton cellulose synthase like D3 (GhCSLD3) gene partially rescued growth defect of atcesa6 mutant with restored cell elongation and cell wall integrity mainly by enhancing primary cellulose production. Among cellulose synthase like (CSL) family proteins, CSLDs share the highest sequence similarity to cellulose synthase (CESA) proteins. Although CSLD proteins have been implicated to participate in the synthesis of carbohydrate-based polymers (cellulose, pectins and hemicelluloses), and therefore plant cell wall formation, the exact biochemical function of CSLD proteins remains controversial and the function of the remaining CSLD genes in other species have not been determined. In this study, we attempted to illustrate the function of CSLD proteins by overexpressing Arabidopsis AtCSLD2, -3, -5 and cotton GhCSLD3 genes in the atcesa6 mutant, which has a background that is defective for primary cell wall cellulose synthesis in Arabidopsis. We found that GhCSLD3 overexpression partially rescued the growth defect of the atcesa6 mutant during early vegetative growth. Despite the atceas6 mutant having significantly reduced cellulose contents, the defected cell walls and lower dry mass, GhCSLD3 overexpression largely restored cell wall integrity (CWI) and improved the biomass yield. Our result suggests that overexpression of the GhCSLD protein enhances primary cell wall synthesis and compensates for the loss of CESAs, which is required for cellulose production, therefore rescuing defects in cell elongation and CWI.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Gossypium/genética , Proteínas de Plantas/fisiologia , Arabidopsis/genética , Arabidopsis/metabolismo , Parede Celular/metabolismo , Celulose/biossíntese , Celulose/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo
10.
Small ; 15(23): e1900902, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31016874

RESUMO

Non-layered tellurium (Te) is a promising material for applications in transistor and optoelectronic devices for its advantages in excellent intrinsic electronic and optoelectronic properties. However, the poor photodetection performance and relatively uncertain stability of tellurene under ambient conditions greatly limit the practical applications. In order to improve the performance of tellurene-based materials, Te@Se roll-to-roll nanotubes with different selenium (Se) contents synthesized by epitaxial growth of Se on Te nanotubes are, for the first time, employed to fabricate working electrodes for photoelectrochemical (PEC)-type broadband photodetection. They exhibit not only a preferably enhanced capacity for self-powered broadband photodetection but also significantly improved photocurrent density and stability in various aqueous environments (HCl, NaCl, and KOH solutions), compared to tellurene-based photodetectors. It is anticipated that the present work can open up new possibilities for high-performance tellurene-based optoelectronic devices.

11.
Hepatology ; 70(4): 1099-1118, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30820969

RESUMO

Nonalcoholic fatty liver disease (NAFLD) has become the most common cause of chronic liver disease worldwide. Due to the growing economic burden of NAFLD on public health, it has become an emergent target for clinical intervention. DUSP12 is a member of the dual specificity phosphatase (DUSP) family, which plays important roles in brown adipocyte differentiation, microbial infection, and cardiac hypertrophy. However, the role of DUSP12 in NAFLD has yet to be clarified. Here, we reveal that DUSP12 protects against hepatic steatosis and inflammation in L02 cells after palmitic acid/oleic acid treatment. We demonstrate that hepatocyte specific DUSP12-deficient mice exhibit high-fat diet (HFD)-induced and high-fat high-cholesterol diet-induced hyperinsulinemia and liver steatosis and decreased insulin sensitivity. Consistently, DUSP12 overexpression in hepatocyte could reduce HFD-induced hepatic steatosis, insulin resistance, and inflammation. At the molecular level, steatosis in the absence of DUSP12 was characterized by elevated apoptosis signal-regulating kinase 1 (ASK1), which mediates the mitogen-activated protein kinase (MAPK) pathway and hepatic metabolism. DUSP12 physically binds to ASK1, promotes its dephosphorylation, and inhibits its action on ASK1-related proteins, JUN N-terminal kinase, and p38 MAPK in order to inhibit lipogenesis under high-fat conditions. Conclusion: DUSP12 acts as a positive regulator in hepatic steatosis and offers potential therapeutic opportunities for NAFLD.

12.
Life Sci ; 224: 12-22, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30872181

RESUMO

AIMS: MicroRNAs (miRNAs or miRs) are a large class of small noncoding RNAs. The present study aims to evaluate the effect of miR-451 on cardiac remodeling in diabetic cardiomyopathy. MAIN METHODS: Mice were injected with streptozotocin (STZ) to induce diabetes. Twelve weeks after final STZ injection, mice were subjected to myocardial injection of adenovirus (Ad)-shmiR-451 to knock down miR-451. Mouse heart endothelial cells (MHECs) were treated with a miR-451 antagomir to inhibit miR451 and were exposed to high glucose. KEY FINDINGS: Sixteen weeks after STZ injection, mice exhibited no significant cardiac hypertrophy but did exhibit serious cardiac fibrosis. MiR-451 knockdown attenuated cardiac fibrosis and improved cardiac function. Moreover, we found that miR-451 knockdown suppressed endothelial-to-mesenchymal transition (EndMT) in diabetic mouse hearts. Hyperglycemia-induced EndMT in MHECs was attenuated by the miR-451 antagomir. Activation of AMPKa1/mTOR was decreased in diabetic mouse heart tissue and hyperglycemia-stimulated MHECs, which was increased following miR-451 knockdown or inhibition. AMPKa1 siRNA abrogated the anti-EndMT effects of miR-451 knockdown in MHECs. SIGNIFICANCE: miR-451 participates in the pathology of diabetic cardiomyopathy via AMPKa1-regulated EndMT in endothelial cells.


Assuntos
Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 1/complicações , Fibrose/terapia , Cardiopatias/terapia , MicroRNAs/antagonistas & inibidores , Substâncias Protetoras , RNA Interferente Pequeno/genética , Animais , Animais Recém-Nascidos , Fibrose/etiologia , Fibrose/genética , Cardiopatias/etiologia , Cardiopatias/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
13.
Adv Mater ; 31(14): e1807981, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30730064

RESUMO

Graphdiyne is a new carbon allotrope comprising sp- and sp2 -hybridized carbon atoms arranged in a 2D layered structure. In this contribution, 2D graphdiyne is demonstrated to exhibit a strong light-matter interaction with high stability to achieve a broadband Kerr nonlinear optical response, which is useful for nonreciprocal light propagation in passive photonic diodes. Furthermore, advantage of the unique Kerr nonlinearity of 2D graphdiyne is taken and a nonreciprocal light propagation device is proposed based on the novel similarity comparison method. Graphdiyne has demonstrated a large nonlinear refractive index in the order of ≈10-5 cm2 W-1 , comparing favorably to that of graphene. Based on the strong Kerr nonlinearity of 2D graphdiyne, a nonlinear photonic diode that breaks time-reversal symmetry is demonstrated to realize the unidirectional excitation of Kerr nonlinearity, which can be regarded as a significant demonstration of a graphdiyne-based prototypical application in nonlinear photonics and might suggest an important step toward versatile graphdiyne-based advanced passive photonics devices in the future.

14.
Nanoscale ; 11(10): 4515-4522, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30806401

RESUMO

An efficient liquid phase exfoliation method has been developed for the preparation of high quality NbSe2 nanosheets. The pure nonlinear optical properties of these nanosheets have been investigated using three different wavelength continuous wave (CW) lasers. The spatial self-phase modulation (SSPM) effect can be observed clearly in solution dispersions of (NbSe2). The experimental data show that the diffraction is caused by the third-order optical nonlinearity of NbSe2. The third-order nonlinearity susceptibility χ(3) of NbSe2 is about 10-9 e.s.u. by analyzing the experimental results. The relaxation time in the dynamic relaxation is about 1.38 s, 1.58 s, and 1.15 s for 532 nm, 671 nm, and 457 nm, respectively. In addition, the realization of all-optical switching based on SSPM, particularly two-color intrachromatic coherence, indicates that the generation of electron coherence is a universal characteristic of layered quantum materials. All optical information conversion based on the SSPM is also confirmed experimentally. Our experimental results have simple potential application prospects for NbSe2 based on its nonlinear optical response.

15.
Nanoscale ; 11(6): 2637-2643, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30698602

RESUMO

In this work, 0-dimensional (0D) CsPbBr3 QDs were integrated with 2D bismuthene having ultrafast carrier mobility, to obtain a 0D/2D nanohybrid. Moreover, an excellent charge transfer efficiency (0.53) and an appreciable quenching constant of 2.3 × 105 M-1 were observed. Tuning the ratio of bismuthene in the Bi/perovskite nanohybrid achieved the quantified control of charge transfer efficiency and quenching performance at the interface.

16.
Nat Commun ; 10(1): 28, 2019 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-30604756

RESUMO

MicroRNA exhibits differential expression levels in cancer and can affect cellular transformation, carcinogenesis and metastasis. Although fluorescence techniques using dye molecule labels have been studied, label-free molecular-level quantification of miRNA is extremely challenging. We developed a surface plasmon resonance sensor based on two-dimensional nanomaterial of antimonene for the specific label-free detection of clinically relevant biomarkers such as miRNA-21 and miRNA-155. First-principles energetic calculations reveal that antimonene has substantially stronger interaction with ssDNA than the graphene that has been previously used in DNA molecule sensing, due to thanking for more delocalized 5s/5p orbitals in antimonene. The detection limit can reach 10 aM, which is 2.3-10,000 times higher than those of existing miRNA sensors. The combination of not-attempted-before exotic sensing material and SPR architecture represents an approach to unlocking the ultrasensitive detection of miRNA and DNA and provides a promising avenue for the early diagnosis, staging, and monitoring of cancer.


Assuntos
Antimônio/química , Técnicas Biossensoriais/instrumentação , Grafite/química , MicroRNAs/isolamento & purificação , Ressonância de Plasmônio de Superfície/instrumentação , Biomarcadores Tumorais/isolamento & purificação , Técnicas Biossensoriais/métodos , DNA de Cadeia Simples/isolamento & purificação , Humanos , Dispositivos Lab-On-A-Chip , Limite de Detecção , Nanoestruturas/química , Neoplasias/diagnóstico , Neoplasias/genética , Sensibilidade e Especificidade , Ressonância de Plasmônio de Superfície/métodos
17.
Sensors (Basel) ; 18(12)2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30558226

RESUMO

Surface exciton polaritons (SEPs) are one of the three major elementary excitations: Phonons, plasmons and excitons. They propagate along the interface of the crystal and dielectric medium. Surface exciton polaritons hold a significant position in the aspect of novel sensor and optical devices. In this article, we have realized a sharp Fano resonance (FR) by coupling the planar waveguide mode (WGM) and SEP mode with Cytop (perfluoro (1-butenyl vinyl ether)) and J-aggregate cyanine dye. After analyzing the coupling mechanism and the localized field enhancement, we then applied our structure to the imaging biosensor. It was shown that the maximum imaging sensitivity of this sensor could be as high as 5858 RIU-1, which is more than three times as much as classical FR based on metal. A biosensor with ultra-high sensitivity, simple manufacturing technique and lower cost with J-aggregate cyanine dye provides us with the most appropriate substitute for the surface plasmon resonance sensors with the noble metals and paves the way for applications in new sensing technology and biological studies.


Assuntos
Técnicas Biossensoriais/métodos , Nanopartículas Metálicas/química
18.
Nanoscale ; 10(44): 20540-20547, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30402631

RESUMO

In recent years, black-phosphorus-analogue (BPA) two-dimensional (2D) materials have been explored to demonstrate promising optoelectronic performances and distinguished ambient stabilities, holding great promise in practical applications. Here, one new kind of BPA material, orthorhombic ß-PbO quantum dots (QDs), is successfully fabricated by a facile liquid phase exfoliation (LPE) technique. The as-prepared ß-PbO QDs show a homogeneous distribution of the lateral size (3.2 ± 0.9 nm) and thickness (2.5 ± 0.5 nm), corresponding to 4 ± 1 layers. The carrier dynamics of ß-PbO QDs was systematically investigated via a femtosecond resolution transient absorption approach in the visible wavelength regime and it was clarified that two decay components were resolved with a decay time of τ1 = 2.3 ± 0.3 ps and τ2 = 87.9 ± 6.0 ps, respectively, providing important insights into their potential applications in the field of ultrafast optics, nanomechanics and optoelectronics. As a proof-of-concept, ß-PbO QDs were, for the first time to our knowledge, fabricated as a working electrode in a photoelectrochemical (PEC)-typed photodetector that exhibits significantly high photocurrent density and excellent stability under ambient conditions.

19.
Opt Lett ; 43(17): 4256-4259, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30160765

RESUMO

The topological edge mode, which exists at the interface of a one-dimensional (1D) topological photonic crystal (PhC) heterostructure, provides the possibility to realize perfect absorption for its strong field localization effects. In this Letter, it is found that a huge absorption enhancement appears because of the excitation of topological edge mode, while the graphene is sandwiched between two 1D PhCs. The single peak perfect absorption is realized by means of the strong coupling of incident light and Tamm plasmon polaritons (TPPs) which is excited with Ag-PhC structure. Moreover, we use a heterostructure constructed by two PhCs, a monolayer graphene and Ag mirror to theoretically demonstrate that multi-channel perfect absorption can be achieved based on the effect of topological edge mode, TPPs and critical coupling. The angular selectivity of the proposed absorber is also investigated. Both of the absorption peaks are extremely narrow, and the absorption can be maintained more than 97% with the incident angle varying from 0° to 50°. Hence, our results may have potential applications in optical switches, thermal emissions, and narrowband selective filters.

20.
Opt Express ; 26(13): 16884-16892, 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-30119507

RESUMO

Fano resonance is realized in the multilayer structure consisting of two planar waveguides (PWGs) and few layer graphene, and the coupling mechanism between the two PWG modes with graphene is analyzed in detail. It is revealed that the Fano resonance originates from the different quality factors due to the different intrinsic losses of the graphene in the two waveguides, and the electric field distributions in the multilayer structure confirms our results. Fano resonance in our proposed structures can be applied in the ultrasensitive biosensor, and a significantly improved figure of merit (FOM) of 9340 RIU-1 has been obtained by optimizing the structure parameters, which has a 2~3 orders of magnitude enhancement compared to the traditional surface plasmon polaritons (SPR) sensor. Especially, it is found that both transverse magnetic (TM)-polarization and transverse electric (TE)-polarization can support the Fano resonance, and hence it can work as ultrasensitive biosensor for both polarizations.

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