DR-NTU (Data) (Nanyang Technological University)
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Related Data for: Immobilizing Polyiodides with Expanded Zn2+ Channels for High-Rate Practical Zinc-Iodine Battery
No full textAqueous zinc-iodine battery (AZIB) has the advantage of low cost and high specific capacity but suffer from the soluble polyiodides shuttling and sluggish redox kinetics. Herein, these two limitations are addressed by employing a cathode additive (zirconium hydrogen phosphate, denoted as EI-ZrP) which provides dual functions: an agent for polyiodide confinement, and abundant channels for zinc ion transport. An enlarged crystalline interlayer (from typical 7.5 to 18.3 Å) of the EI-ZrP significantly enhances the ionic conductivity and simultaneously immobilizes polyiodides, leading to an accelerated conversion process. AZIB with EI-ZrP in the iodine cathode exhibits a high capacity retention over 10,000 cycles (with a 0.02‰ decay rate per cycle). Quasi-solid-state Zn-I2 pouch cell has been constructed using hydrogel-paper as separator and EI-ZrP additive, which delivers a high areal capacity under repeated bending. As a proof-of-concept demonstration, the paper battery is integrated to power a wireless flexible pressure sensor system (WFPSS). This strategy may shed light on the rational design of conversion-type cathode materials for both energy storage and flexible portable electronics
Related Data for: Multi-IRS Empowered Terahertz Wireless Communication over Generalized Fading
No full textIntelligent reflecting surfaces (IRS) have emerged as a promising technology for addressing the inherent challenges associated with terahertz (THz) bands, thereby enhancing system performance and offering immense potential for future wireless systems. However, existing single and multi-IRS-aided wireless systems often overlook crucial IRS-related factors such as IRS unit-cell dimensions, IRS gain, and inter-IRS collaboration, potentially limiting system performance. To mitigate these limitations and leverage the unique advantages of the THz band, this study investigates a multi-IRS-empowered THz system that incorporates design parameters such as transceiver antenna gains, operation frequency, link distances, molecular absorption losses, beam misalignment, transceiver hardware imperfections, and statistical characteristics of the THz channel. By utilizing a sophisticated channel model that integrates the joint effects of these parameters with IRS properties and inter-IRS collaboration, this study demonstrates significant enhancement in system performance and power savings. Moreover, exact closed-form expressions and asymptotic approximations for outage probability are derived to quantify the effects of the deterministic and statistical channel parameters. These findings provide valuable insights into the practical implementation of multi-IRS-assisted THz networks, contributing to ongoing efforts to unlock the potential of the THz band for future wireless applications
Replication Data for: Stable and Highly Emissive Infrared Yb-doped Perovskite Quantum Cutters Engineered by Machine Learning
No full textQuantum cutting (QC) allows the conversion of high-energy photons into lower-energy photons, exhibiting great potential for infrared communications. Yb-doped perovskite nanocrystals can achieve an efficient QC process with extremely high photoluminescence quantum yield (PLQY) thanks to the favorable Yb3+ incorporation in the perovskite structure. However, conventionally used oleic acid–oleylamine-based ligand pairs cause instability issues due to highly dynamic binding to surface states that have curbed their potential applications. Herein, zwitterionic type C3-sulfobetaine 3-(N,N-Dimethylpalmitylammonio)propanesulfonate molecule is utilized to build a strong binding state on the nanocrystals’ surface through a new phosphine oxide synthesis route. Leveraging machine learning and Bayesian Optimization workflow to determine optimal synthesis conditions, near-infrared PLQY above 190% is achieved. The high PLQY is well maintained after over three months of aging, under high-flux continuous UV irradiation, and long continuous annealing. This is the first report of highly efficient and stable perovskite quantum cutters, which will drive the study of fundamental physics phenomena and near-infrared quantum communications
Replication Data for: Unravelling the Factors Influencing Halide Perovskite Based Switchable Photovoltaics
No full textLead halide perovskites have revolutionized the field of optoelectronics (such as photovoltaics and light emitting diodes) demonstrating extraordinary material properties despite being formed at low temperatures. However, ion migration in the bulk or at the interfaces results in stability issues especially in devices where metal electrodes directly interface with the perovskite film. Utilizing the switchable photovoltaic phenomenon (SPV) in halide perovskites as a measure of ion migration and electrochemical reactions within them, Cs0.05MA0.15FA0.70PbI2.5Br0.5 triple cation perovskite, widely used in photovoltaics is evaluated. The various factors determining the SPV, including electric field magnitudes, type of metal contacts, Illumination conditions, and temperature is systematically measured. This study reveals the roles of electrode work functions and reactivities on ion migration and local electronic structure modulation. ITO electrodes demonstrated the highest open-circuit voltage (Voc) about 0.85 V while Ag electrodes developed conductive filaments. However, the Voc distribution for Ti and Cr electrodes shows a more pronounced linear correlation with the poling electric field strength. Insights from this lateral design are directly relevant to transistor and memristor architectures and offer inputs into the design of perovskite-based photovoltaic/optoelectronic devices
ClearCLIP: Decomposing CLIP Representations for Dense Vision-Language Inference
No full textDespite the success of large-scale pretrained Vision-Language Models (VLMs) especially CLIP in various open-vocabulary tasks, their application to semantic segmentation remains challenging, producing noisy segmentation maps with mis-segmented regions. In this paper, we carefully re-investigate the architecture of CLIP, and identify residual connections as the primary source of noise that degrades segmentation quality. With a comparative analysis of statistical properties in the residual connection and the attention output across different pretrained models, we discover that CLIP’s image-text contrastive training paradigm emphasizes global features at the expense of local discriminability, leading to noisy segmentation results. In response, we propose ClearCLIP, a novel approach that decomposes CLIP’s representations to enhance open-vocabulary semantic segmentation. We introduce three simple modifications to the final layer: removing the residual connection, implementing the self-self attention, and discarding the feed-forward network. ClearCLIP consistently generates clearer and more accurate segmentation maps and outperforms existing approaches across multiple benchmarks, affirming the significance of our discoveries
Replication Data for: ReVersion: Diffusion-Based Relation Inversion from Images
No full textA replication of the ReVersion Benchmark, for the paper "ReVersion: Diffusion-Based Relation Inversion from Images"
Establishing an end-to-end workflow for SNSPD fabrication and characterization
No full textThe outstanding performance of superconducting nanowire single-photon detectors (SNSPDs) has expanded their application areas from quantum technologies to astronomy, space communication, imaging, and LiDAR. As a result, there has been a surge in demand for these devices, that commercial products cannot readily meet. Consequently, more research and development efforts are being directed towards establishing in-house SNSPD manufacturing, leveraging existing nano-fabrication capabilities that can be customized and fine-tuned for specific needs. We report on the implementation of an end-to-end workflow for SNSPD fabrication and characterization, from superconducting film growth to meander nanowire fabrication and their integration with electrical readout circuits and optical testbeds. An essential aspect of this research involved identifying the key parameters of our workflow and developing reliable procedures for their optimization. As an outcome, the ab initio development of SNSPD technology yielded devices with characteristics comparable to commercial devices at a wavelength of 1550 nm, making them well-suited for telecommunication and integrated quantum systems. This report aims to provide useful insights to those entering the field and accelerate the establishment of superconducting detector technology and its application across various domains
Replication Data for: Enhancing X-ray generation from twisted multilayer van der Waals materials by shaping electron wavepackets
No full textSimulation data for bremsstrahlung differential cross sections for all relavant figures in the published article "Enhancing X-ray generation from twisted multilayer van der Waals materials by shaping electron wavepackets
Related Data for: Wearable EEG-Based Brain–Computer Interface for Stress Monitoring
No full textDataset comprised EEG and ECG data collected from 40 subjects performing MMIT and CVT Tasks as described in the paper