Dexerials (Japan)

Integration of photogrammetry and light detection and ranging (LiDAR) algorithms has garnered attention to enhance visual fidelity and geometric accuracy in three-dimensional (3D) modeling. Here we show an ultralight 10 g solid-state single-photon LiDAR that minimizes photon cost per measurement. Achieving a maximum indoor distance of 25 m and a point cloud density of ~3.16 Mpps, the LiDAR provides geometric fidelity, while maintaining fine structure information challenging for conventional LiDAR. Key embedded components include a Q-switching semiconductor laser, which emits a 50-ps pulse-width tail-free laser using bandgap renormalization. A four-channel time-to-digital converter achieves a 3 ps timing jitter per channel and features real-time time-walk error correction for Poisson-distributed photon counts. A low-Q two-dimensional (2D) MEMS mirror with a 20 mm2 mirror size and precisely controlled feedforward-driven frequency enables non-repetitive scanning and super-dense point cloud generation. We present 3D modeling using the colored point clouds and discuss its characteristics and challenges.

High-speed modulators are key devices in optical transceivers for communication. The demands for higher capacity, miniaturization, and lower power consumption in transceivers have required modulators to simultaneously achieve high speed, high efficiency, and compact integration. Although these improvements are challenging due to intertwined performance metrics, various methods have been explored in recent years in terms of materials and device structures.

Rational ligand design enabled comprehensive passivation of perovskite nanocrystals, boosting LED performance, and underscoring its transformative potential.

ABSTRACT In this study, we selectively removed fluoride ions (F−) from simulated iodine-containing wastewater using zirconium silicate (ZrSiO4). Zirconium silicate could selectively adsorb F− in solutions with coexisting anions such as sulfate, chloride, bromide, iodine, and borate. The simulated iodine-containing catalytic wastewater contained fluoride (2.6 mmol/L (50 mg/L)) and iodine (630 mmol/L (80 g/L)) ions with the pH adjusted to 2 using sulfuric acid. Fluoride was selectively adsorbed from the simulated iodine-containing wastewater to final concentrations of below the target value to recover iodine for fluoride (0.42 mmol/L (8 mg/L)) with iodine remaining at the initial concentration (630 mmol/L). The desorption of fluoride using an alkaline solution (NaOH) was more effective than with using NH3 and Na2CO3, and the cycle stability of the adsorbent was high. ZrSiO4 granules can be prepared from ZrSiO4 powder using water glass binder by heating at 400°C. In the chromatographic separation analysis, F− were effectively adsorbed on the adsorbent packed into the column, whereas iodine ions (I−) were scarcely adsorbed. In the desorption stage, the concentration of F− was seven times that of the initial concentration in the feed solution in the adsorption stage, whereas little iodine was eluted. A molar selectivity coefficient of F−/I− of up to 1600 was achieved.

In response to the growing awareness of a circular economy, various tools for measuring circularity have been developed. Nonetheless, most tools are only useful for measuring circularity at the company-level. The available product-level tools require company specific and often sensitive data, which limits the possibility of using these tools for benchmarking in a commercial context. As companies are pressured to develop more circular products, understanding their market position with respect to their major competitors will help them develop a circular product strategy. This study created and tested a circularity toolset for benchmarking consumer electronics. Its target groups are corporate designers and engineers in the electronics industry. The aim of this paper is to describe the circularity toolset and results of the case study. Product circularity is difficult to measure with a single tool because of its broad concept. Therefore, we developed a new tool (Product Journey Mapping tool) and adapted existing tools (Circular Product Readiness tool and Disassembly Map tool) for benchmarking. These tools correspond to three levels of product circularity: product flow (macro-level), business strategy (meso-level) and product design (micro-level). A case study using two headphones was conducted to confirm the usefulness of the toolset. Through benchmarking headphones with the toolset, we got a comprehensive analysis of circularity based on quantitative and qualitative findings.

The purpose of this technical presentation is to investigate thermal management solutions used to solve thermal performance limitations of power modules and high-power processors, such as GPUs for autonomous driving. With the rise in computing and power electronics in automobiles, the need for heat dissipation increases. The challenges include decreasing package sizes, creating fan-less system requirements, and higher ambient operating temperatures. Existing thermal interface material (TIM) range from gap pads, thermal grease, liquid-dispensed TIM, and phase-change material. Dexerials will introduce a gap pad TIM with carbon fiber for automotive applications and propose novel thermal management setups to reduce thermal resistance, keep system cooling requirements to a minimum, and maintain optimal system performance over lifetime of the product.

Non-Hermitian physics is an emerging field that for the unconventional management and control of wave fields. PT-symmetric metamaterials or dipoles have already been proposed as a flexible platform to redirect electromagnetic fields. Acoustic PT-dipoles have also been recently studied for sound guidance, showing an asymmetric scattering response. Therefore, we experimentally propose pairs of identical Helmholtz resonators with different losses distributed in the plane to create such dipoles (as electromagnetic analogues) and either concentrate the field, redirect it or even silence predefined areas. The experimental results confirm that the two-dimensional sound pressure field can be successfully modified on the bases of non-Hermitian physics.

Quantum-confined cesium lead tribromide perovskite quantum dots (PeQDs) are attractive photonic sources for versatile optoelectronic devices and thus the synthetic routes have been explored via various techniques. However, the lack of a general method to fabricate the quantum-confined PeQD with remarkable stability at colloidal state has been one of the major obstacles to device applications. Herein, we propose a simple and robust ligand-assisted reprecipitation method associated with didodecyl dimethyl ammonium bromide for quantum-confined PeQDs with remarkable stability at colloidal state. This method will shed a light on the field of colloidal PeQDs synthesis for the next generation of photonic sources.

Despite the excellent performance of neural-network-based audio source separation methods and their wide range of applications, their robustness against intentional attacks has been largely neglected. In this work, we reformulate various adversarial attack methods for the audio source separation problem and intensively investigate them under different attack conditions and target models. We further propose a simple yet effective regularization method to obtain imperceptible adversarial noise while maximizing the impact on separation quality with low computational complexity. Experimental results show that it is possible to largely degrade the separation quality by adding imperceptibly small noise when the noise is crafted for the target model. We also show the robustness of source separation models against a black-box attack. This study provides potentially useful insights for developing content protection methods against the abuse of separated signals and improving the separation performance and robustness.