A new strategy of using pre-grown crystals to study preferential adsorption of various additives is demonstrated for the electrocrystallization of Cu2O. In this method, micron-size Cu2O crystals with well-defined cubic and octahedral shapes were first electrochemically grown, and their crystallization was resumed in a medium containing the additive to be investigated (e.g., Na+, NH4+, SO42-, Cl-, dodecyl sulfate). This method makes it possible to systematically study the interaction of additives with specific planes (e.g., {100} of a cube and {111} of an octahedron) already present. By observing shape transformation over time, the relative stabilities of {100}, {111}, and {110} planes of Cu2O in various growth media could be determined. During this study, a general scheme of forming new crystal shapes containing crystallographic planes that cannot be directly stabilized by preferential adsorption alone was also established (i.e., rhombicuboctahedral shape of Cu2O containing {110} planes). This method can ...

Elucidating the effect of additives on the growth and stability of Cu2O surfaces via shape transformation of pre-grown crystals

Efficient second harmonic generation in integrated platforms is usually achieved by resonant structures, intermodal phase-matching or quasi-phase matching by periodically poling ferroelectric waveguides. However, in all these structures, it is impossible to reconfigure the phase-matching condition in an all-optical way. Here, we demonstrate that a Watt-level laser causes a periodic modification of the second-order susceptibility in a silicon nitride waveguide, allowing for quasi-phase-matching between the pump and second harmonic modes for arbitrary wavelengths inside the erbium band. The grating is long-term inscribed, and leads to a second harmonic generation enhancement of more than 30 dB. We estimate a χ
 (2)
 on the order of 0.3 pm/V, with a maximum conversion efficiency of 0.05% W−1. We explain the observed phenomenon with the coherent photogalvanic effect model, which correctly agrees with the retrieved experimental parameters. Phase-matching and quasi-phase-matching in periodically poled ferroelectrics ensure efficient harmonic generation, but only statically. Here, Billat et al. demonstrate all-optically reconfigurable second harmonic generation by inscribing a stable grating in CMOS-compatible nonlinear waveguides.

/pdf/large-second-harmonic-generation-enhancement-in-si3n4-31tf44n8bg.pdf

Large second harmonic generation enhancement in Si3N4 waveguides by all-optically induced quasi-phase-matching.

Integrated waveguides exhibiting efficient second-order nonlinearities are crucial to obtain compact and low power optical signal processing devices. Silicon nitride (SiN) has shown second harmonic generation (SHG) capabilities in resonant structures and single-pass devices leveraging intermodal phase matching, which is defined by waveguide design. Lithium niobate allows compensating for the phase mismatch using periodically poled waveguides, however the latter are not reconfigurable and remain difficult to integrate with SiN or silicon (Si) circuits. Here we show the all-optical enhancement of SHG in SiN waveguides by more than 30 dB. We demonstrate that a Watt-level laser causes a periodic modification of the waveguide second-order susceptibility. The resulting second order nonlinear grating has a periodicity allowing for quasi phase matching (QPM) between the pump and SH mode. Moreover, changing the pump wavelength or polarization updates the period, relaxing phase matching constraints imposed by the waveguide geometry. We show that the grating is long term inscribed in the waveguides, and we estimate a second order nonlinearity of the order of 0.3 pm/V, while a maximum conversion efficiency (CE) of 1.8x10-6 W-1 cm-2 is reached.

/pdf/large-second-harmonic-generation-enhancement-in-sin-b9gpxxs2vy.pdf

Large second harmonic generation enhancement in SiN waveguides by all-optically induced quasi phase matching

Optical and transport properties of nonstoichiometric tantalum oxide thin films grown by ion beam deposition were investigated in order to understand the dominant charge transport mechanisms and reveal the nature of traps. The TaOx films composition was analyzed by X-ray photoelectron spectroscopy and by quantum-chemistry simulation. From the optical absorption and photoluminescence measurements and density functional theory simulations, it was concluded that the 2.75 eV blue luminescence excited in a TaOx by 4.45 eV photons, originates from oxygen vacancies. These vacancies are also responsible for TaOx conductivity. The thermal trap energy of 0.85 eV determined from the transport experiments coincides with the half of the Stokes shift of the blue luminescence band. It is argued that the dominant charge transport mechanism in TaOx films is phonon-assisted tunneling between the traps.

Charge Transport and the Nature of Traps in Oxygen Deficient Tantalum Oxide.

The electronic properties of HfO2, in particular, luminescence and charge transport, are determined by defects and traps. The origin of luminescence centers and traps of charge carriers in a HfO2 crystal was studied using luminescence spectroscopy, charge transport, and quantum-chemical calculation. The 2.7 eV luminescence band and 5.2 eV absorption/luminescence excitation band are associated with an oxygen vacancy. The thermal activation energy 1.25 eV, estimated from the charge transport and thermoluminescence experiment, is equal to half of the Stokes shift in photoluminescence spectra. Hence, oxygen vacancies are supposed to operate as electron traps in HfO2, and the charge transport is described by phonon-assisted tunneling between traps.

Oxygen Vacancy in Hafnia as a Blue Luminescence Center and a Trap of Charge Carriers

Silicon oxide and silicon nitride are two key dielectrics in silicon devices. The advantage of Si3N4 over other dielectrics is that silicon nitride is compatible with silicon technology. It is required to study in detail the charge transport mechanism in a Si3N4-based memristor to further improve the cell element and to create a matrix of these elements. Despite many research activities carried out, the charge transport mechanism in Si3N4-based memristors is still unclear. Metal–nitride–oxide–silicon structures that exhibit memristor properties were obtained using low-pressure chemical vapor deposition at 700 °C. The fabricated metal–nitride–oxide–silicon memristor structure does not require a forming procedure. In addition, the metal–nitride–oxide–silicon memristor has a memory window of about five orders of magnitude. We found that the main charge transport mechanism in the metal–nitride–oxide–silicon memristor in a high resistive state is the model of space-charge-limited current with traps. In a low resistive state, the charge transport mechanism is described by the space-charge-limited current model with filled traps. Trap parameters were determined in the Si3N4-based memristor in the high resistive state.

Charge transport mechanism in the metal–nitride–oxide–silicon forming-free memristor structure

Surface Energy and Crystal Faceting of Elemental Semiconductors and Other Substances

Metal-nitride-oxide-silicon structures that exhibit memristor properties were obtained using the low-pressure chemical vapor deposition at 700° C. The fabricated metal-nitride-oxide-silicon memristor structure does not require a forming procedure. In addition, the metal-nitride-oxide-silicon memristor has a memory window of about 3 orders of magnitude. In our work, the charge transport of high and low resistive states in a metal-nitride-oxide-silicon memristor is analyzed with two contact-limited models and six bulk-limited charge transport models. It is established that the Schottky effect model, thermally assisted tunneling model, Frenkel model of Coulomb traps ionization, Hill-Adachi model of overlapping Coulomb traps, Shklovskii-Efros percolation model, Makram-Ebeid and Lannoo model of multiphonon isolated traps ionization and the Nasyrov-Gritsenko model of phonon-assisted tunneling between traps, quantitatively, do not describe the charge transport of metal-nitride-oxide-silicon memristor. We found that the main charge transport mechanism in the metal-nitride-oxide-silicon memristor in a high resistive state is the model of space-charge-limited current with traps. In a low resistive state, the charge transport mechanism is described by the space-charge-limited current model with filled traps.

/pdf/the-peculiarities-of-cellular-automata-visualization-in-es4y6j58pc.pdf

The peculiarities of cellular automata visualization in nanoelectronics

Structural complexes formed in the Si-SiO2 boundary layer under high-temperature thermal oxidation of silicon are considered A mathematical model of the kinetics of silicon-oxygen cluster polymerization was suggested using the boundary-layer concept The influence of the diffusion flow of these clusters on the percentage of SiO4 tetrahedral chains of various lengths in the SiO2 bulk was noted

Mathematical simulation of the kinetics of high-temperature silicon oxidation and the structure of the boundary layer in the Si-SiO2 system

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

G. Ya. Krasnikov

Author Tools

Chat about Author

Papers

Charge transport mechanism in the metal–nitride–oxide–silicon forming-free memristor structure

Surface Energy and Crystal Faceting of Elemental Semiconductors and Other Substances

Charge transport mechanism in the metal–nitride–oxide–silicon forming-free memristor structure

The peculiarities of cellular automata visualization in nanoelectronics

Mathematical simulation of the kinetics of high-temperature silicon oxidation and the structure of the boundary layer in the Si-SiO2 system