Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Susceptibility, Permittivity and Dielectric Constant01:26

Susceptibility, Permittivity and Dielectric Constant

3.7K
When placed in an external electric field, a dielectric material gets polarized. The charge density in the dielectric material is given by the sum of the bound and free charge densities, while the total charge density can also be written in terms of the total electric field. The bound charge density can be measured in terms of polarization, leading to the relationship between electric displacement and polarization.
3.7K
Dielectric Polarization in a Capacitor01:31

Dielectric Polarization in a Capacitor

6.8K
The presence of a dielectric medium in a capacitor not only changes the voltage and capacitance but also affects the electric field. In general, dielectrics can be of two types: polar and nonpolar. In a polar dielectric, the positive and negative charges in the molecules are separated by a distance and hence have a permanent dipole moment. In contrast, no such charge separation exists in a nonpolar dielectric, however the nonpolar molecules get polarized in the presence of an external electric...
6.8K
Capacitor With A Dielectric01:18

Capacitor With A Dielectric

5.6K
Parallel plate capacitors consist of two conducting plates separated by a certain distance. However, it is mechanically difficult to hold the large plates parallel to each other without actual contact. Hence, a dielectric layer is commonly placed between the plates, which provides an easy solution for holding the plates together with a small gap and increases the capacitance of the capacitor.
Dielectrics are non-conducting materials with no free or loosely bound electrons. When a dielectric is...
5.6K
Types of Semiconductors01:20

Types of Semiconductors

1.9K
Intrinsic semiconductors are highly pure materials with no impurities. At absolute zero, these semiconductors behave as perfect insulators because all the valence electrons are bound, and the conduction band is empty, disallowing electrical conduction. The Fermi level is a concept used to describe the probability of occupancy of energy levels by electrons at thermal equilibrium. In intrinsic semiconductors, the Fermi level is positioned at the midpoint of the energy gap at absolute zero. When...
1.9K
Electrostatic Boundary Conditions in Dielectrics01:27

Electrostatic Boundary Conditions in Dielectrics

2.1K
When an electric field passes from one homogeneous medium to another, crossing the boundary between the two mediums imparts a discontinuity in the electric field. This results in electrostatic boundary conditions that depend on the type of mediums the field propagates through.
Consider a case where both the mediums across a boundary are two different dielectric materials. Recall that the electric field and electric displacement are proportional and related through the material's permittivity....
2.1K
MOS Capacitor01:25

MOS Capacitor

1.9K
A Metal-Oxide-Semiconductor (MOS) capacitor is a fundamental structure used extensively in semiconductor device technology, particularly in the fabrication of integrated circuits and MOSFETs (metal-oxide-semiconductor field-effect transistors). The MOS capacitor consists of three layers: a metal gate, a dielectric oxide, and a semiconductor substrate.
The metal gate is typically made from highly conductive materials such as aluminum or polysilicon. Beneath the metal gate lies a thin layer of...
1.9K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Plasmon-Induced Hot-State Multiexciton Emission from Quantum Dots Coupled to Metallic Nanocavities.

ACS nano·2026
Same author

Nature inspired design methodology for a wide field of view achromatic metalens.

Nanophotonics (Berlin, Germany)·2025
Same author

Wafer-scale integration of photonic integrated circuits and atomic vapor cells.

Nanophotonics (Berlin, Germany)·2025
Same author

Silicon rich nitride: a platform for controllable structural colors.

Nanophotonics (Berlin, Germany)·2025
Same author

Suppressing the Decoherence of Alkali-Metal Spins at Low Magnetic Fields.

Physical review letters·2025
Same author

Waveguide-integrated mid-IR photodetector and all-optical modulator based on interlayer excitons absorption in a WS<sub>2</sub>/HfS<sub>2</sub> heterostructure.

Nanophotonics (Berlin, Germany)·2024

Related Experiment Video

Updated: Apr 20, 2026

Demonstration of Equal-Intensity Beam Generation by Dielectric Metasurfaces
09:33

Demonstration of Equal-Intensity Beam Generation by Dielectric Metasurfaces

Published on: June 7, 2019

6.8K

Mode conversion based on dielectric metamaterial in silicon.

David Ohana, Uriel Levy

    Optics Express
    |November 18, 2014
    PubMed
    Summary

    We developed a novel silicon waveguide mode converter using a graded index grating coupler. This device efficiently couples different light modes with high purity and low crosstalk, enabling advanced photonic applications.

    Area of Science:

    • Photonics
    • Materials Science
    • Optical Engineering

    Background:

    • Mode converters are crucial for manipulating light in photonic integrated circuits.
    • Existing silicon waveguide mode converters face challenges in efficiency and bandwidth.

    Purpose of the Study:

    • To propose, design, and analyze a novel silicon waveguide mode converter.
    • To achieve efficient coupling between different symmetric and asymmetric modes.

    Main Methods:

    • Design based on a graded index co-directional grating coupler.
    • Realization of graded index profile using nanoscale dielectric metamaterials.
    • Analysis using coupled mode theory (CMT) and effective medium theory (EMT).
    • Validation through 3D finite difference time domain (FDTD) simulations.

    More Related Videos

    Demonstration of Spin-Multiplexed and Direction-Multiplexed All-Dielectric Visible Metaholograms
    08:48

    Demonstration of Spin-Multiplexed and Direction-Multiplexed All-Dielectric Visible Metaholograms

    Published on: September 25, 2020

    6.4K
    Application of a Coupling Agent to Improve the Dielectric Properties of Polymer-Based Nanocomposites
    06:34

    Application of a Coupling Agent to Improve the Dielectric Properties of Polymer-Based Nanocomposites

    Published on: September 19, 2020

    6.5K

    Related Experiment Videos

    Last Updated: Apr 20, 2026

    Demonstration of Equal-Intensity Beam Generation by Dielectric Metasurfaces
    09:33

    Demonstration of Equal-Intensity Beam Generation by Dielectric Metasurfaces

    Published on: June 7, 2019

    6.8K
    Demonstration of Spin-Multiplexed and Direction-Multiplexed All-Dielectric Visible Metaholograms
    08:48

    Demonstration of Spin-Multiplexed and Direction-Multiplexed All-Dielectric Visible Metaholograms

    Published on: September 25, 2020

    6.4K
    Application of a Coupling Agent to Improve the Dielectric Properties of Polymer-Based Nanocomposites
    06:34

    Application of a Coupling Agent to Improve the Dielectric Properties of Polymer-Based Nanocomposites

    Published on: September 19, 2020

    6.5K

    Main Results:

    • High mode purity (96%) and transmission (>96%).
    • Low crosstalk (< -23dB) with the input mode.
    • Compact device length (20µm) and ~25nm spectral bandwidth around 1550nm.

    Conclusions:

    • The proposed graded index grating coupler offers a highly efficient and compact solution for mode conversion in silicon waveguides.
    • The device demonstrates excellent performance metrics, suitable for integrated photonic applications.
    • The use of metamaterials and effective medium theory provides a pathway for advanced photonic device design.