Video Experimental Relacionado
Updated: May 9, 2026
08:39
Shaping the Amplitude and Phase of Laser Beams by Using a Phase-only Spatial Light Modulator
Published on: January 28, 2019
Materiales activos no lineales: una ilustración de la compatibilidad de fase controlable
Hongcheng Lu1, Romain Gautier, Martin D Donakowski
1State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University, 127 Youyixilu Road, Xi'an 710072, China.
Journal of the American Chemical Society
|July 20, 2013
Resumen
El descubrimiento de cristales ópticos no lineales (NLO) compatibles en fase es clave. Este estudio muestra la estructura cristalina, no solo la eficiencia, determina si los materiales NLO son compatibles con la fase (PM) para aplicaciones prácticas.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- La cristalografía es una técnica de cristalografía.
- La óptica es la óptica.
Sus antecedentes:
- Los cristales ópticos no lineales (NLO) son cruciales para aplicaciones como la generación de segundo armónico (SHG).
- Para su uso práctico, los cristales NLO deben ser no centrosimétricos (NCS) y compatibles con la fase (PM).
- La investigación previa se centró en la creación de compuestos NCS y la mejora de la eficiencia de SHG, a menudo descuidando la compatibilidad de fase.
Objetivo del estudio:
- Investigar el origen de la coincidencia de fases en los materiales híbridos NCS.
- Para sintetizar y comparar dos compuestos NCS químicamente similares con diferentes compatibilidad de fase.
- Determinar el papel de la disposición molecular en el logro de la compatibilidad de fase.
Principales métodos:
- Síntesis de dos nuevos compuestos híbridos: [Hdpa]2NbOF5·2H2O y HdpaNbOF4.
- Análisis cristalográfico para confirmar la estructura NCS para ambos compuestos.
- Comparación de la compatibilidad de fase (PM vs. no PM) de los materiales sintetizados.
Principales resultados:
- Se ha confirmado que ambos compuestos sintetizados, [Hdpa]2NbOF5·2H2O y HdpaNbOF4, son NCS.
- Se encontró que el compuesto (I) no es PM, mientras que el compuesto químicamente similar (II) es PM.
- La disposición de la molécula orgánica (dpa) dentro de la estructura cristalina dicta la compatibilidad de fase.
Conclusiones:
- La disposición precisa de los componentes orgánicos en los cristales NCS híbridos es fundamental para lograr la compatibilidad de fase.
- Este hallazgo proporciona una nueva dirección para el diseño de materiales NLO prácticos y compatibles en fase.
- Los principios de la cristalografía orgánica son vitales para comprender y predecir la coincidencia de fases en los sistemas NLO híbridos.
Videos de Conceptos Relacionados
02:31Phase Transitions
Whether solid, liquid, or gas, a substance's state depends on the order and arrangement of its particles (atoms, molecules, or ions). Particles in the solid pack closely together, generally in a pattern. The particles vibrate about their fixed positions but do not move or squeeze past their neighbors. In liquids, although the particles are closely spaced, they are randomly arranged. The position of the particles are not fixed—that is, they are free to move past their neighbors to occupy...
01:24Time and frequency -Domain Interpretation of Phase-lead Control
Phase-lead controllers are commonly used in various control systems to enhance response speed and stability. Adjusting the brightness on a television screen offers a practical example of phase-lead control. When contrast is enhanced, a phase-lead controller is employed. Mathematically, phase-lead control is identified when the first parameter is smaller than the second.
The design of phase-lead control involves the strategic placement of poles and zeros to balance steady-state error and system...
The design of phase-lead control involves the strategic placement of poles and zeros to balance steady-state error and system...
01:19Phase Diagram
The phase of a given substance depends on the pressure and temperature. Thus, plots of pressure versus temperature showing the phase in each region provide considerable insights into the thermal properties of substances. Such plots are known as phase diagrams. For instance, in the phase diagram for water (Figure 1), the solid curve boundaries between the phases indicate phase transitions (i.e., temperatures and pressures at which the phases coexist).
02:39Phase Diagrams
A phase diagram combines plots of pressure versus temperature for the liquid-gas, solid-liquid, and solid-gas phase-transition equilibria of a substance. These diagrams indicate the physical states that exist under specific conditions of pressure and temperature and also provide the pressure dependence of the phase-transition temperatures (melting points, sublimation points, boiling points). Regions or areas labeled solid, liquid, and gas represent single phases, while lines or curves represent...
01:19Phase Changes
Phase transitions play an important theoretical and practical role in the study of heat flow. In melting or fusion, a solid turns into a liquid; the opposite process is freezing. In evaporation, a liquid turns into a gas; the opposite process is condensation.
A substance melts or freezes at a temperature called its melting point and boils or condenses at its boiling point. These temperatures depend on pressure. High pressure favors the denser form of the substance, so typically, high pressure...
A substance melts or freezes at a temperature called its melting point and boils or condenses at its boiling point. These temperatures depend on pressure. High pressure favors the denser form of the substance, so typically, high pressure...
01:26Phase Contrast and Differential Interference Contrast Microscopy
Phase-Contrast Microscopes
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...