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1.
Plant Cell ; 36(8): 2908-2926, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-38835286

RESUMO

N 6-methyladenosine (m6A) is the most abundant mRNA modification and plays diverse roles in eukaryotes, including plants. It regulates various processes, including plant growth, development, and responses to external or internal stress responses. However, the mechanisms underlying how m6A is related to environmental stresses in both mammals and plants remain elusive. Here, we identified EVOLUTIONARILY CONSERVED C-TERMINAL REGION 8 (ECT8) as an m6A reader protein and showed that its m6A-binding capability is required for salt stress responses in Arabidopsis (Arabidopsis thaliana). ECT8 accelerates the degradation of its target transcripts through direct interaction with the decapping protein DECAPPING 5 within processing bodies. We observed a significant increase in the ECT8 expression level under various environmental stresses. Using salt stress as a representative stressor, we found that the transcript and protein levels of ECT8 rise in response to salt stress. The increased abundance of ECT8 protein results in the enhanced binding capability to m6A-modified mRNAs, thereby accelerating their degradation, especially those of negative regulators of salt stress responses. Our results demonstrated that ECT8 acts as an abiotic stress sensor, facilitating mRNA decay, which is vital for maintaining transcriptome homeostasis and enhancing stress tolerance in plants. Our findings not only advance the understanding of epitranscriptomic gene regulation but also offer potential applications for breeding more resilient crops in the face of rapidly changing environmental conditions.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Estabilidade de RNA , Arabidopsis/genética , Arabidopsis/fisiologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Estabilidade de RNA/genética , Estresse Fisiológico/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Estresse Salino/genética , Adenosina/análogos & derivados , Adenosina/metabolismo , Plantas Geneticamente Modificadas
2.
PLoS Genet ; 18(9): e1010386, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36166469

RESUMO

Adenosine bases of RNA can be transiently modified by the deposition of a methyl-group to form N6-methyladenosine (m6A). This adenosine-methylation is an ancient process and the enzymes involved are evolutionary highly conserved. A genetic screen designed to identify suppressors of late flowering transgenic Arabidopsis plants overexpressing the miP1a microProtein yielded a new allele of the FIONA1 (FIO1) m6A-methyltransferase. To characterize the early flowering phenotype of fio1 mutant plants we employed an integrative approach of mRNA-seq, Nanopore direct RNA-sequencing and meRIP-seq to identify differentially expressed transcripts as well as differentially methylated RNAs. We provide evidence that FIO1 is the elusive methyltransferase responsible for the 3'-end methylation of the FLOWERING LOCUS C (FLC) transcript. Furthermore, our genetic and biochemical data suggest that 3'-methylation stabilizes FLC mRNAs and non-methylated FLC is a target for rapid degradation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Regiões 3' não Traduzidas/genética , Adenosina/genética , Adenosina/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Histonas/genética , Proteínas de Domínio MADS/genética , Proteínas de Domínio MADS/metabolismo , Metilação , Metiltransferases/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
3.
Nano Lett ; 24(1): 254-260, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38133576

RESUMO

The remarkable ultrathin ability of metalenses gives them potential as a next-generation imaging candidate. However, the inherent chromatic aberration of metalenses restricts their widespread application. We present an achromatic metalens with optoelectronic computing fusion (OCF) to mitigate the impact of chromatic aberration and simultaneously avoid the significant challenges of nanodesign, nanofabrication, and mass production of metalenses, a method different from previous methods. Leveraging the nonlinear fitting, we demonstrate that OCF can effectively learn the chromatic aberration mapping of metalens and thus restore the chromatic aberration. In terms of the peak signal-to-noise ratio index, there is a maximum improvement of 12 dB, and ∼8 ms is needed to correct the chromatic aberration. Furthermore, the edge extraction of images and super-resolution reconstruction that effectively enhances resolution by a factor of 4 are also demonstrated with OCF. These results offer the possibility of applications of metalenses in mobile cameras, virtual reality, etc.

4.
Nano Lett ; 24(7): 2408-2414, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38329291

RESUMO

Two-dimensional (2D) heterostructures with ferromagnetism and ferroelectricity provide a promising avenue to miniaturize the device size, increase computational power, and reduce energy consumption. However, the direct synthesis of such eye-catching heterostructures has yet to be realized up to now. Here, we design a two-step chemical vapor deposition strategy to growth of Cr2S3/WS2 vertical heterostructures with atomically sharp and clean interfaces on sapphire. The interlayer charge transfer and periodic moiré superlattice result in the emergence of room-temperature ferroelectricity in atomically thin Cr2S3/WS2 vertical heterostructures. In parallel, long-range ferromagnetic order is discovered in 2D Cr2S3 via the magneto-optical Kerr effect technique with the Curie temperature approaching 170 K. The charge distribution variation induced by the moiré superlattice changes the ferromagnetic coupling strength and enhances the Curie temperature. The coexistence of ferroelectricity and ferromagnetism in 2D Cr2S3/WS2 vertical heterostructures provides a cornerstone for the further design of logic-in-memory devices to build new computing architectures.

5.
BMC Plant Biol ; 24(1): 181, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38468197

RESUMO

BACKGROUND: The era of high throughput sequencing offers new paths to identifying species boundaries that are complementary to traditional morphology-based delimitations. De novo species delimitation using traditional or DNA super-barcodes serve as efficient approaches to recognizing putative species (molecular operational taxonomic units, MOTUs). Tea plants (Camellia sect. Thea) form a group of morphologically similar species with significant economic value, providing the raw material for tea, which is the most popular nonalcoholic caffeine-containing beverage in the world. Taxonomic challenges have arisen from vague species boundaries in this group. RESULTS: Based on the most comprehensive sampling of C. sect. Thea by far (165 individuals of 39 morphospecies), we applied three de novo species delimitation methods (ASAP, PTP, and mPTP) using plastome data to provide an independent evaluation of morphology-based species boundaries in tea plants. Comparing MOTU partitions with morphospecies, we particularly tested the congruence of MOTUs resulting from different methods. We recognized 28 consensus MOTUs within C. sect. Thea, while tentatively suggesting that 11 morphospecies be discarded. Ten of the 28 consensus MOTUs were uncovered as morphospecies complexes in need of further study integrating other evidence. Our results also showed a strong imbalance among the analyzed MOTUs in terms of the number of molecular diagnostic characters. CONCLUSION: This study serves as a solid step forward for recognizing the underlying species boundaries of tea plants, providing a needed evidence-based framework for the utilization and conservation of this economically important plant group.


Assuntos
Camellia sinensis , Camellia , Humanos , Código de Barras de DNA Taxonômico/métodos , Camellia sinensis/genética , Chá/genética , DNA , Filogenia
6.
Small ; : e2402575, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860359

RESUMO

Effective and rapid heat transfer is critical to improving electronic components' performance and operational stability, particularly for highly integrated and miniaturized devices in complex scenarios. However, current thermal manipulation approaches, including the recent advancement in thermal metamaterials, cannot realize fast and unidirectional heat flow control. In addition, any defects in thermal conductive materials cause a significant decrease in thermal conductivity, severely degrading heat transfer performance. Here, the utilization of silicon-based valley photonic crystals (VPCs) is proposed and numerically demonstrated to facilitate ultrafast, unidirectional heat transfer through thermal radiation on a microscale. Utilizing the infrared wavelength region, the approach achieves a significant thermal rectification effect, ensuring continuous heat flow along designed paths with high transmission efficiency. Remarkably, the process is unaffected by temperature gradients due to the unidirectional property, maintaining transmission directionality. Furthermore, the VPCs' inherent robustness affords defect-immune heat transfer, overcoming the limitations of traditional conduction methods that inevitably cause device heating, performance degradation, and energy waste. The design is fully CMOS compatible, thus will find broad applications, particularly for integrated optoelectronic devices.

7.
Plant Biotechnol J ; 22(9): 2410-2423, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38634166

RESUMO

The N6-methyladenosine (m6A) mRNA modification is crucial for plant development and stress responses. In rice, the male sterility resulting from the deficiency of OsFIP37, a core component of m6A methyltransferase complex, emphasizes the significant role of m6A in male fertility. m6A is reversible and can be removed by m6A demethylases. However, whether mRNA m6A demethylase regulates male fertility in rice has remained unknown. Here, we identify the mRNA m6A demethylase OsALKBH9 and demonstrate its involvement in male fertility regulation. Knockout of OsALKBH9 causes male sterility, dependent on its m6A demethylation activity. Cytological analysis reveals defective tapetal programmed cell death (PCD) and excessive accumulation of microspores exine in Osalkbh9-1. Transcriptome analysis of anthers shows up-regulation of genes involved in tapetum development, sporopollenin synthesis, and transport pathways in Osalkbh9-1. Additionally, we demonstrate that OsALKBH9 demethylates the m6A modification in TDR and GAMYB transcripts, which affects the stability of these mRNAs and ultimately leads to excessive accumulation of pollen exine. Our findings highlight the precise control of mRNA m6A modification and reveal the pivotal roles played by OsALKBH9-mediated m6A demethylation in tapetal PCD and pollen exine accumulation in rice.


Assuntos
Desmetilação , Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Pólen , Oryza/genética , Oryza/metabolismo , Pólen/genética , Pólen/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Adenosina/análogos & derivados , Adenosina/metabolismo , Apoptose/genética , Infertilidade das Plantas/genética
8.
Opt Express ; 32(7): 11221-11240, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38570975

RESUMO

Laser-guided detector and infrared detection have attracted increasing attention in a wide range of research fields, including multispectral detection, radiative cooling, and thermal management. Previously reported absorbers presented shortcomings of lacking either tunability or compatibility. In this study, a metamaterial perfect absorber based on a Helmholtz resonator and fractal structure is proposed, which realizes tunable perfect absorptivity (α 1.06µ m >0.99,α 10.6µ m >0.99) of guided-laser radar dual operating bands (1.06 µm and 10.6 µm) and a low infrared average emissivity (ε¯3-5µ m =0.03,ε¯8-14µ m =0.31) in two atmospheric windows for compatible camouflage. The proposed perfect absorber provides a dynamically tunable absorptivity without structural changes and can be applied to optical communication, military stealth or protection, and electromagnetic detection.

9.
Opt Express ; 32(12): 21400-21411, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38859494

RESUMO

Multi-mode multiplexing optical interconnection (MMOI) has been widely used as a new technology that can significantly expand communication bandwidth. However, the constant-on state of each channel in the existing MMOI systems leads to serious interference for receivers when extracting and processing information, necessitating introducing real-time selective-on function for each channel in MMOI systems. To achieve this goal, combining several practical requirements, we propose a real-time selective mode switch based on phase-change materials, which can individually tune the passing/blocking of different modes in the bus waveguide. We utilize our proposed particle swarm optimization algorithm with embedded neural network surrogate models (NN-in-PSO) to design this mode switch. The proposed NN-in-PSO significantly reduces the optimization cost, enabling multi-dimensional simultaneous optimization. The resulting mode switch offers several advantages, including ultra-compactness, rapid tuning, nonvolatility, and large extinction ratio. Then, we demonstrate the real-time channel selection function by integrating the mode switch into the MMOI system. Finally, we prove the fabricating robustness of the proposed mode switch, which paves the way for its large-scale application.

10.
Opt Express ; 32(3): 3379-3393, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297560

RESUMO

In contrast to conventional emitters fashioned from traditional materials, tunable thermal emitters exhibit a distinct propensity to fulfill the demands of diverse scenarios, thereby engendering an array of prospects within the realms of communications, military applications, and control systems. In this paper, a tunable thermal emitter without continuous external excitation is introduced using Ge2Sb2Te5 (GST) and high-temperature-resistant material Mo. It is automatically optimized by inverse design with genetic algorithm (GA) to switch between different functions according to the object temperature to adapt to diverse scenarios. In "off" mode, the emitter orchestrates a blend of infrared (IR) stealth and thermal management. This is evidenced by average absorptivity values of 0.08 for mid-wave infrared (MIR, 3-5 µm), 0.19 for long-wave infrared (LIR, 8-14 µm), and 0.68 for the non-atmospheric window (NAW, 5-8 µm). Conversely, when confronted with high-temperature entities, the emitter seamlessly transitions to "on" mode, instigating a process of radiative cooling. This transformation is reflected in the augmented emissivity of the dual-band atmospheric window including MIR and LIR, attaining peak values of 0.96 and 0.97. This transition yields a cooling potential, quantified at 64 W/m2 at the ambient temperature of 25°C. In addition, our design employs a layered structure, which avoids complex patterned resonators and facilitates large-area fabrication. The emitter in this paper evinces robust insensitivity to polarization variations and the angle of incidence. We believe that this work will contribute to the development in the fields of dynamic tunability for IR stealth, dynamic radiative cooling systems, and thermal imaging.

11.
Opt Express ; 32(6): 9456-9467, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571180

RESUMO

Traditional optical information recognition (OIR), particle capture and manipulation require many optical devices or mechanical moving system components to achieve a specific function, which is difficult to achieve integration. This paper proposes a new method to realize these functions by using multi-focus metalens combining spectrum and polarization selection. The design incorporates three spectral bands, namely 500 nm, 580 nm, and 660 nm, within the visible light range. Additionally, it utilizes either left-handed or right-handed circularly polarized (LCP/RCP) light, resulting in six distinct focus focusing effects on a single focal plane. By analyzing the normalized light intensity (NLI) at the corresponding focus position, the OIR of any wavelength and polarization detection in the design can be realized, and the particle capture at different focusing positions can be realized. Our work can provide a new idea for the high integration of on-chip light recognition and operation and inspire the design of a highly integrated optical system with a smaller size and more substantial function.

12.
Opt Express ; 32(6): 8506-8519, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571108

RESUMO

In this paper, a 1 × 2 photonic switch is designed based on a silicon-on-insulator (SOI) platform combined with the phase change material (PCM), Sb2S3, assisted by the direct binary search (DBS) algorithm. The designed photonic switch exhibits an impressive operating bandwidth ranging from 1450 to 1650 nm. The device has an insertion loss (IL) from 0.44 dB to 0.70 dB (of less than 0.7 dB) and cross talk (CT) from -26 dB to -20 dB (of less than -20 dB) over an operating bandwidth of 200 nm, especially an IL of 0.52 dB and CT of -24 dB at 1550 nm. Notably, the device is highly compact, with footprints of merely 3 × 4 µm2. Furthermore, we have extended the device's functionality for multifunctional operation in the C-band that can serve as both a 1 × 2 photonic switch and a 3 dB photonic power splitter. In the photonic switch mode, the device demonstrates an IL of 0.7 dB and a CT of -13.5 dB. In addition, when operating as a 3 dB photonic power splitter, the IL is less than 0.5 dB.

13.
Opt Lett ; 49(11): 2958-2961, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824302

RESUMO

Mode converters, crucial elements within photonic integrated circuits (PICs) designed for multimode optical transmission and switching systems, present a challenge due to their bulky structures in thin-film lithium niobate (TFLN) integrated platforms, which are incompatible with the compact and efficient nature desired for dense PICs. In this work, we propose TE1-TE0, TE2-TE0, and TE3-TE0 mode converters in shallowly etched TFLN, within small footprints. The experimental results show that the insertion loss is 0.4 dB, 0.6 dB, and 0.5 dB for the compact TE1-TE0, TE2-TE0, and TE3-TE0 mode converters, respectively, and these devices can be operated within a wide 1 dB bandwidth (BW) over 100 nm. This work facilitates the development of low-loss, broadband, and compact monolithically integrated photonic devices for future multimode communication networks in TFLN integrated platforms.

14.
BMC Cancer ; 24(1): 1187, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39334021

RESUMO

N6-methyladenosine (m6A) is a prevalent mRNA modification known for its implications in various cancer types, yet its role in chromophobe renal cell carcinoma (chRCC) remains largely unexplored. In this study, we performed m6A-SEAL-seq and RNA-seq analyses on tissues from three chRCC subjects, aiming to uncover m6A alterations in chRCC. Our findings revealed reduced expression levels of four m6A regulators in chRCC tissues and highlighted differences in m6A levels compared to normal tissues. Furthermore, we identified specific genes and cancer-related pathways affected by these differences, including notable candidates like NOTCH1 and FGFR1, implicated in chRCC development. Additionally, we developed a predictive model based on the expression level of m6A associated genes, demonstrating promising prognostic capabilities for patient survival prediction. Overall, our study provides valuable insights into the role of m6A in chRCC and its potential as a prognostic indicator.


Assuntos
Adenosina , Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/metabolismo , Neoplasias Renais/mortalidade , Neoplasias Renais/genética , Neoplasias Renais/patologia , Neoplasias Renais/metabolismo , Adenosina/análogos & derivados , Adenosina/metabolismo , Prognóstico , Regulação Neoplásica da Expressão Gênica , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Masculino , Feminino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Perfilação da Expressão Gênica
15.
Am J Bot ; 111(2): e16276, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38297448

RESUMO

PREMISE: Dioecy (separate sexes) has independently evolved numerous times across the angiosperm phylogeny and is recently derived in many lineages. However, our understanding is limited regarding the evolutionary mechanisms that drive the origins of dioecy in plants. The recent and repeated evolution of dioecy across angiosperms offers an opportunity to make strong inferences about the ecological, developmental, and molecular factors influencing the evolution of dioecy, and thus sex chromosomes. The genus Asparagus (Asparagaceae) is an emerging model taxon for studying dioecy and sex chromosome evolution, yet estimates for the age and origin of dioecy in the genus are lacking. METHODS: We use plastome sequences and fossil time calibrations in phylogenetic analyses to investigate the age and origin of dioecy in the genus Asparagus. We also review the diversity of sexual systems present across the genus to address contradicting reports in the literature. RESULTS: We estimate that dioecy evolved once or twice approximately 2.78-3.78 million years ago in Asparagus, of which roughly 27% of the species are dioecious and the remaining are hermaphroditic with monoclinous flowers. CONCLUSIONS: Our findings support previous work implicating a young age and the possibility of two origins of dioecy in Asparagus, which appear to be associated with rapid radiations and range expansion out of Africa. Lastly, we speculate that paleoclimatic oscillations throughout northern Africa may have helped set the stage for the origin(s) of dioecy in Asparagus approximately 2.78-3.78 million years ago.


Assuntos
Evolução Biológica , Cromossomos Sexuais , Filogenia , África , África do Norte
16.
Nano Lett ; 23(5): 1758-1766, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36790274

RESUMO

Two-dimensional (2D) nanosheet arrays with unidirectional orientations are of great significance for synthesizing wafer-scale single crystals. Although great efforts have been devoted, the growth of atomically thin magnetic nanosheet arrays and single crystals is still unaddressed. Here we design an interisland-distance-mediated chemical vapor deposition strategy to synthesize centimeter-scale atomically thin Fe3O4 arrays with unidirectional orientations on mica. The unidirectional alignment of nearly all the Fe3O4 nanosheets is driven by a dual-coupling-guided growth mechanism. The Fe3O4/mica interlayer interaction induces two preferred antiparallel orientations, whereas the interisland interaction of Fe3O4 breaks the energy degeneracy of antiparallel orientations. The room-temperature long-range ferrimagnetic order and thickness-tunable magnetic domain evolution are uncovered in atomically thin Fe3O4. This strategy to tune the orientations of nanosheets through the an interisland interaction can guide the synthesis of other 2D transition-metal oxides, thereby laying a solid foundation for future spintronic device applications at the integration level.

17.
Int J Mol Sci ; 25(16)2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39201691

RESUMO

The genus Amomum includes over 111 species, 6 of which are widely utilized as medicinal plants and have already undergone taxonomic revision. Due to their morphological similarities, the presence of counterfeit and substandard products remains a challenge. Accurate plant identification is, therefore, essential to address these issues. This study utilized 11 newly sequenced samples and extensive NCBI data to perform molecular identification of the six medicinal "Doukou" species. The plastomes of these species exhibited a typical quadripartite structure with a conserved gene content. However, independent variation shifts of the SC/IR boundaries existed between and within species. The comprehensive set of genetic sequences, including ITS, ITS1, ITS2, complete plastomes, matK, rbcL, psbA-trnH, and ycf1, showed varying discrimination of the six "Doukou" species based on both distance and phylogenetic tree methods. Among these, the ITS, ITS1, and complete plastome sequences demonstrated the highest identification success rate (3/6), followed by ycf1 (2/6), and then ITS2, matK, and psbA-trnH (1/6). In contrast, rbcL failed to identify any species. This research established a basis for a reliable molecular identification method for medicinal "Doukou" plants to protect wild plant resources, promote the sustainable use of medicinal plants, and restrict the exploitation of these resources.


Assuntos
Filogenia , Plantas Medicinais , Plantas Medicinais/genética , Plantas Medicinais/classificação , Análise de Sequência de DNA/métodos , Genomas de Plastídeos
18.
Small ; 19(38): e2302029, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37194986

RESUMO

Sodium-ion batteries (SIBs) have received increasing attention because of their appealing cell voltages and cost-effective features. However, the atom aggregation and electrode volume variation inevitably deteriorate the sodium storage kinetics. Here a new strategy is proposed to boost the lifetime of SIB by synthesizing sea urchin-like FeSe2 /nitrogen-doped carbon (FeSe2 /NC) composites. The robust FeN coordination hinders the Fe atom aggregation and accommodates the volume expansion, while the unique biomorphic morphology and high conductivity of FeSe2 /NC enhance the intercalation/deintercalation kinetics and shorten the ion/electron diffusion length. As expected, FeSe2 /NC electrodes deliver excellent half (387.6 mAh g-1 at 20.0 A g-1 after 56 000 cycles) and full (203.5 mAh g-1 at 1.0 A g-1 after 1200 cycles) cell performances. Impressively, an ultralong lifetime of SIB composed of FeSe2 /Fe3 Se4 /NC anode is uncovered with the cycle number exceeding 65 000. The sodium storage mechanism is clarified with the aid of density function theory calculations and in situ characterizations. This work hereby provides a new paradigm for enhancing the lifetime of SIB by constructing a unique coordination environment between active material and framework.

19.
Opt Express ; 31(10): 15904-15916, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157681

RESUMO

Optical power splitters with ultra-broadband and ultra-low insertion loss are desired in the field of photonic integration. Combining two inverse design algorithms for staged optimization, we present the design of a Y-junction photonic power splitter with 700 nm wavelength bandwidth (from 1200 nm to 1900 nm) within a 0.2 dB insertion loss, corresponding to a 93 THz frequency bandwidth. The average insertion loss is approximately -0.057 dB in the valuable C-band. Moreover, we comprehensively compared the insertion loss performance of different types and sizes of curved waveguides, and also give the cases of 1:4 and 1:6 cascaded power splitters. These scalable Y-junction splitters provide new alternatives for high-performance photonic integration.

20.
Opt Express ; 31(18): 29235-29244, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710728

RESUMO

In this work, we use the inverse design method to design three-channel and four-channel dual-mode waveguide crossings with the design regions of 4.32 µm-wide regular hexagon and 6.68 µm-wide regular octagon, respectively. Based on the highly-symmetric structures, the fundamental transverse electric (TE0) and TE1 modes propagate through the waveguide crossings efficiently. Moreover, the devices are practically fabricated and experimentally characterized. The measured insertion losses and crosstalks of the three-channel and dual-mode waveguide crossing for both the TE0 and TE1 modes are less than 1.8 dB and lower than -18.4 dB from 1540 nm to 1560 nm, respectively. The measured insertion losses of the four-channel and dual-mode waveguide crossing for the TE0 and TE1 modes are less than 1.8 dB and 2.5 dB from 1540 nm to 1560 nm, respectively, and the measured crosstalks are lower than -17.0 dB. In principle, our proposed scheme can be extended to waveguide crossing with more channels and modes.

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