A 256 Gb/s electronic−photonic monolithically integrated transceiver in 45 nm CMOS

With the explosive development of artificial intelligence(AI),machine learning(ML),and high-performance comput-ing(HPC),the ever-growing data movement is asking for high density interconnects with higher bandwidth(BW),lower power and lower latency[1−3].The optical I/O leverages silicon photonic(SiPh)technology to enable high-density large-scale integrated photonics.

Low-Loss 256-Channel AWG Module with Monolithically Integrated Spot-Size Converters

We developed a compact fiber-pigtailed 256-channel AWG module with 1.5% A waveguides. By monolithically integrating spot-size converters with input/output waveguides, we achieved a low insertion loss of 2.6-4.1 dB with a low background crosstalk of-40 dB.

Challenges and Opportunities in Preserving Key Structural Features of 3D-Printed Metal/Covalent Organic Framework

Metal-organic framework(MOF)and covalent organic framework(COF)are a huge group of advanced porous materials exhibiting attractive and tunable microstructural features,such as large surface area,tunable pore size,and functional surfaces,which have significant values in various application areas.The emerging 3D printing technology further provides MOF and COFs(M/COFs)with higher designability of their macrostructure and demonstrates large achievements in their performance by shaping them into advanced 3D monoliths.However,the currently available 3D printing M/COFs strategy faces a major challenge of severe destruction of M/COFs’microstructural features,both during and after 3D printing.It is envisioned that preserving the microstructure of M/COFs in the 3D-printed monolith will bring a great improvement to the related applications.In this overview,the 3D-printed M/COFs are categorized into M/COF-mixed monoliths and M/COF-covered monoliths.Their differences in the properties,applications,and current research states are discussed.The up-to-date advancements in paste/scaffold composition and printing/covering methods to preserve the superior M/COF microstructure during 3D printing are further discussed for the two types of 3D-printed M/COF.Throughout the analysis of the current states of 3D-printed M/COFs,the expected future research direction to achieve a highly preserved microstructure in the 3D monolith is proposed.

Hybrid Strategy of Partitioned and Monolithic Methods for Solving Strongly Coupled Analysis of Inverse and Direct Piezoelectric and Circuit Coupling

The inverse and direct piezoelectric and circuit coupling are widely observed in advanced electro-mechanical systems such as piezoelectric energy harvesters.Existing strongly coupled analysis methods based on direct numerical modeling for this phenomenon can be classified into partitioned or monolithic formulations.Each formulation has its advantages and disadvantages,and the choice depends on the characteristics of each coupled problem.This study proposes a new option:a coupled analysis strategy that combines the best features of the existing formulations,namely,the hybrid partitioned-monolithic method.The analysis of inverse piezoelectricity and the monolithic analysis of direct piezoelectric and circuit interaction are strongly coupled using a partitioned iterative hierarchical algorithm.In a typical benchmark problem of a piezoelectric energy harvester,this research compares the results from the proposed method to those from the conventional strongly coupled partitioned iterative method,discussing the accuracy,stability,and computational cost.The proposed hybrid concept is effective for coupled multi-physics problems,including various coupling conditions.

Surface-functionalized hole-selective monolayer for high efficiency single-junction wide-bandgap and monolithic tandem perovskite solar cells

Carbazole moiety-based 2PACz([2-(9H-carbazol-9-yl)ethyl]phosphonic acid)self-assembled monolayers(SAMs)are excellent hole-selective contact(HSC)materials with abilities to excel the charge-transferdynamics of perovskite solar cells(PSCs).Herein,we report a facile but powerful method to functionalize the surface of 2PACz-SAM,by which reproducible,highly stable,high-efficiency wide-bandgap PSCs can be obtained.The 2PACz surface treatment with various donor number solvents improves assembly of 2PACz-SAM and leave residual surface-bound solvent molecules on 2PACz-SAM,which increases perovskite grain size,retards halide segregation,and accelerates hole extraction.The surface functionalization achieves a high power conversion efficiency(PCE)of 17.62%for a single-junction wide-bandgap(~1.77 e V)PSC.We also demonstrate a monolithic all-perovskite tandem solar cell using surfaceengineered HSC,showing high PCE of 24.66%with large open-circuit voltage of 2.008 V and high fillfactor of 81.45%.Our results suggest this simple approach can further improve the tandem device,when coupled with a high-performance narrow-bandgap sub-cell.

Resilient performance of self-centering hybrid rocking walls with curved interface under pseudo-static loading

Frame and rocking wall(FRW)structures have excellent resilient performance during earthquakes.However,the concrete at interfacial corners of rocking walls(RWs)is easily crushed due to local extreme compression during the rocking process.An innovative RW with a curved interface is proposed to prevent interfacial corners from producing local damage,enhancing its earthquake resilient performance(ERP).The precast wall panel with a curved interface is assembled into an integral self-centering hybrid rocking wall(SCRW)by two post-tensioned unbonded prestressed tendons.Moreover,two ordinary energy dissipation steel rebars and two shear reinforcements are arranged to increase the energy dissipation capacity and lateral resistance.Two SCRW specimens and one monolithic reinforced concrete(RC)shear wall(SW)were tested under pseudo-static loading to compare the ERPs of the proposed SCRW and the SW,focusing on studying the effect of the curved interface on the SCRW.The key resilient performance of rocking effects,failure modes,and hysteretic properties of the SCRW were explored.The results show that nonlinear deformations of the SCRW are concentrated along the interface between the SCRW and the foundation,avoiding damage within the SCRW.The restoring force provided by the prestressed tendons can effectively realize self-centering capacity with small residual deformation,and the resilient performance of the SCRW is better than that of monolithic SW.In addition,the curved interface of the SCRW makes the rocking center change and move inward,partially relieving the stress concentration and crush of concrete.The rocking range of the rocking center is about 41.4%of the width of the SCRW.

Experiments in Modernizing Cob Construction

This paper will discuss experiments using various forming systems combined with utilizing mechanical equipment,from cement mixers to excavators and skid steers with attachments,to accelerate construction of cob homes and greatly reduce the labor involved.Cob is a colloquial term for monolithic adobe,and refers to a masonry building technique used since ancient times that uses locally-sourced clay as a binder,with various aggregates from sand to small grit or stone,woven together with straw or other fiber and built in continuous layers to form a monolithic structure.

Monolithically integrated dual-wavelength photodetector based on a step-shaped Fabry-Prot filter

A novel long wavelength photodetector with dual-wavelength spectral response is designed and fabricated using a step-shaped Fabry-Perot （F-P） filter structure. The step-shaped GaAs/A1GaAs distributed Bragg reflectors and the InP PIN photodetector are grown on a GaAs substrate using low pressure metal organic chemical vapor deposition. High quality GaAs/InP heteroepitaxy is realized by employing a thin low temperature buffer layer. The photodetector structure is optimized by theoretical simulation. This device has a dual-peak distance of 19 nm （1558 and 1 577 nm）. The 3-dB bandwidth of 16 GHz is simultaneously obtained with peak ouantum efficiencies of 8.5% and 8.6% around 1 .55R and 1 .577 nm respectively

A Review of Innovative Design Strategies for Prefabricated Green Buildings

Prefabricated green buildings are becoming a trend in the construction industry of China.The prefabricated components are made using modern technologies like green materials,artificial intelligence,and low-carbon and energy-saving techniques.This makes them an important aspect of the development of the construction industry in China,representing modernization and sustainable development.This article presents a study on the innovative design of prefabricated green buildings.This article serves to promote sustainable development on a macro level.

A monolithically sculpted van der Waals nano-opto-electro-mechanical coupler

The nano-opto-electro-mechanical systems(NOEMS)are a class of hybrid solid devices that hold promises in both classical and quantum manipulations of the interplay between one or more degrees of freedom in optical,electrical and mechanical modes.To date,studies of NOEMS using van der Waals(vdW)heterostructures are very limited,although vdW materials are known for emerging phenomena such as spin,valley,and topological physics.Here,we devise a universal method to easily and robustly fabricate vdW heterostructures into an architecture that hosts opto-electro-mechanical couplings in one single device.We demonstrated several functionalities,including nano-mechanical resonator,vacuum channel diodes,and ultrafast thermo-radiator,using monolithically sculpted graphene NOEMS as a platform.Optical readout of electric and magnetic field tuning of mechanical resonance in a CrOCl/graphene vdW NOEMS is further demonstrated.Our results suggest that the introduction of the vdW heterostructure into the NOEMS family will be of particular potential for the development of novel lab-on-a-chip systems.

Monolithically integrated CoP nanowire array： An on/off switch for effective on-demand hydrogen generation via hydrolysis of NaBH4 and NH3BH3

The issues of hydrogen generation and storage have hindered the widespread use and commercialization of hydrogen fuel cell vehicles. It is thus highly attractive, but the design and development of highly active non-noble-metal catalysts for on-demand hydrogen release from alkaline NaBH4 solution under mild conditions remains a key challenge. Herein, we describe the use of CoP nanowire array integrated on a Ti mesh （CoP NA/Ti） as a three-dimensional （3D） monolithic catalyst for efficient hydrolytic dehydrogenation of NaBH4 in basic solutions. The CoP NAFFi works as an on/off switch for on-demand hydrogen generation at a rate of 6,500 mL/（min.g） and a low activation energy of 41 kJ/mol. It is highly robust for repeated usage after recycling, without sacrificing catalytic performance. Remarkably, this catalyst also performs efficiently for the hydrolysis of NH3BH3.

Highly integrated photonic crystal bandedge lasers monolithically grown on Si substrates

Monolithic integration of Ⅲ-Ⅴ lasers with small footprint, good coherence, and low power consumption based on a CMOS-compatible Si substrate have been known as an efficient route towards high-density optical interconnects in the photonic integrated circuits. However, the material dissimilarities between Si and Ⅲ-Ⅴ materials limit the performance of monolithic microlasers. Here, under the pumping condition of a continuous-wave 632.8 nm He–Ne gas laser at room temperature, we achieved an InAs/GaAs quantum dot photonic crystal bandedge laser, which is directly grown on an on-axis Si(001) substrate, which provides a feasible route towards a low-cost and large-scale integration method for light sources on the Si platform.

Technology challenges for monolithically integrated waveguide demultiplexers

A short overview of integrated waveguide demultiplexers for different applications in future highly integrated optical communication systems is presented. Some fabricated devices based on amorphous silicon nanowire technology are described.

4 × 40 GHz mode-locked laser diode array monolithically integrated with an MMI combiner

We report a distributed-Bragg-reflectors-based 4 × 40 GHz mode-locked laser diode(MLLD) array monolithically integrated with a multimode interference(MMI) combiner. The laser produces 2.98 ps pulses with a timebandwidth product of 0.39. The peak wavelength of the MLLD array can be tuned by 8.4 nm while maintaining a good mode-locked state. The four mode-locked channels could work simultaneously with the peak wavelength interval around 3 nm.

A 1.55-μm laser array monolithically integrated with an MMI combiner

The monolithic integration of four 1.55-μm range InGaAsP/InP distributed feedback lasers with a 4× 1 multimode-interference （MMI） optical combiner using the varied width ridge method is proposed and demonstrated. The average output power is 1.5 mW when the current of LD is 100 mA and the threshold current is 30-35 mA at 25 ℃. The lasing wavelength is 1.55-μm range and 40 dB sidemode suppression ratio is obtained. The four channels can operate separately or simultaneously.

Boosting Capacitive Deionization Performance of Commercial Carbon Fibers Cloth via Structural Regulation Based on Catalytic-Etching Effect

Monolithic carbon electrodes with robust mechanical integrity and porous architecture are highly desired for capacitive deionization but remain challenging.Owing to the excellent mechanical strength and electroconductivity,commercial carbon fibers cloth demonstrates great potential as high-performance electrodes for ions storage.Despite this,its direct application on capacitive deionization is rarely reported in terms of limited pore structure and natural hydrophobicity.Herein,a powerful metal-organic framework-engaged structural regulation strategy is developed to boost the desalination properties of carbon fibers.The obtained porous carbon fibers features hierarchical porous structure and hydrophilic surface providing abundant ions-accessible sites,and continuous graphitized carbon core ensuring rapid electrons transport.The catalytic-etching mechanism involving oxidation of Co and subsequent carbonthermal reduction is proposed and highly relies on annealing temperature and holding time.When directly evaluated as a current collector-free capacitive deionization electrode,the porous carbon fibers demonstrates much superior desalination capability than pristine carbon fibers,and remarkable cyclic stability up to 20 h with negligible degeneration.Particularly,the PCF-1000 showcases the highest areal salt adsorption capacity of 0.037 mg cm^(−2) among carbon microfibers.Moreover,monolithic porous carbon fibers-carbon nanotubes with increased active sites and good structural integrity by in-situ growth of carbon nanotubes are further fabricated to enhance the desalination performance(0.051 mg cm^(−2)).This work demonstrates the great potential of carbon fibers in constructing high-efficient and robust monolithic electrode for capacitive deionization.

Flexible Nanocomposite Conductors for Electromagnetic Interference Shielding

With the extensive use of electronic communication technology in integrated circuit systems and wearable devices, electromagnetic interference(EMI) has increased dramatically. The shortcomings of conventional rigid EMI shielding materials include high brittleness, poor comfort, and unsuitability for conforming and deformable applications. Hitherto, flexible(particularly elastic) nanocomposites have attracted enormous interest due to their excellent deformability. However, the current flexible shielding nanocomposites present low mechanical stability and resilience, relatively poor EMI shielding performance, and limited multifunctionality. Herein, the advances in low-dimensional EMI shielding nanomaterials-based elastomers are outlined and a selection of the most remarkable examples is discussed. And the corresponding modification strategies and deformability performance are summarized. Finally, expectations for this quickly increasing sector are discussed, as well as future challenges.

High surface area biocarbon monoliths for methane storage

New energy sources that reduce the volume of harmful gases such as SO_(x)and NO_(x)released into the atmosphere are in constant development.Natural gas,primarily made up of methane,is being widely used as one reliable energy source for heating and electricity generation due to its high combustion value.Currently,natural gas accounts for a large portion of electricity generation and chemical feedstock in manufacturing plastics and other commercially important organic chemicals.In the near future,natural gas will be widely used as a fuel for vehicles.Therefore,a practical storage device for its storage and transportation is very beneficial to the deployment of natural gas as an energy source for new technologies.In this tutorial review,biomaterials-based carbon monoliths(CMs),one kind of carbonaceous material,was reviewed as an adsorbent for natural gas(methane)adsorption and storage.

Efficiency-loss analysis of monolithic perovskite/silicon tandem solar cells by identifying the patterns of a dual two-diode model’s current-voltage curves

In this work,we developed a simple and direct circuit model with a dual two-diode model that can be solved by a SPICE numerical simulation to comprehensively describe the monolithic perovskite/crystalline silicon(PVS/c-Si)tandem solar cells.We are able to reveal the effects of different efficiency-loss mechanisms based on the illuminated current density-voltage(J-V),semi-log dark J-V,and local ideality factor(m-V)curves.The effects of the individual efficiency-loss mechanism on the tandem cell’s efficiency are discussed,including the exp(V/VT)and exp(V/2VT)recombination,the whole cell’s and subcell’s shunts,and the Ohmic-contact or Schottky-contact of the intermediate junction.We can also fit a practical J-V curve and find a specific group of parameters by the trial-and-error method.Although the fitted parameters are not a unique solution,they are valuable clues for identifying the efficiency loss with the aid of the cell’s structure and experimental processes.This method can also serve as an open platform for analyzing other tandem solar cells by substituting the corresponding circuit models.In summary,we developed a simple and effective methodology to diagnose the efficiency-loss source of a monolithic PVS/c-Si tandem cell,which is helpful to researchers who wish to adopt the proper approaches to improve their solar cells.

A benzenesulfonic acid-modified organic polymer monolithic column with reversed-phase/hydrophilic bifunctional selectivity for capillary electrochromatography

Here,a styrene-based polymer monolithic column poly(VBS-co-TAT-co-AHM)with reversed-phase/hydrophilic interaction liquid chromatography(RPLC/HILIC)bifunctional separation mode was success-fully prepared for capillary electrochromatography by the in situ polymerization of sodium p-styrene sulfonate(VBS)with cross-linkers 3-(acryloyloxy)-2-hydroxypropyl methacrylate(AHM)and 1,3,5-triacryloylhexahydro-1,3,5-triazine(TAT).The preparation conditions of the monolith were optimized.The morphology and formation of the poly(VBS-co-TAT-co-AHM)monolith were confirmed by scanning electron microscopy(SEM)and Fourier transform infrared spectroscopy(FT-IR).The separation perfor-mances of the monolith were evaluated systematically.It should be noted that the incorporation of VBS functional monomer can provideπ-πinteractions,hydrophilic interactions,and ion-exchange in-teractions.Hence,the prepared poly(VBS-co-TAT-co-AHM)monolith can achieve efficient separation of thiourea compounds,benzene series,phenol compounds,aniline compounds and sulfonamides in RPLC or HILIC separation mode.The largest theoretical plate number for N,N0-dimethylthiourea reached 1.7×10^(5)plates/m.In addition,the poly(VBS-co-TAT-co-AHM)monolithic column showed excellent reproducibility and stability.This novel monolithic column has great application value and potential in capillary electrochromatography(CEC).