Related Experiment Video

Updated: Aug 15, 2026

Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing
10:42

Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing

Published on: March 22, 2019

Impact of valence band offset on optical transitions and carrier dynamics in LWIR InAs/InAsSb nBn detectors

K Murawski, G Kołodziej, B Seredyński

    Optics Express
    |August 14, 2026
    PubMed

    More Related Videos

    Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations13:56

    Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations

    Published on: October 12, 2019

    High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy10:40

    High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy

    Published on: June 28, 2016

    Related Concept Videos

    IR Absorption Frequency: Hybridization01:21

    IR Absorption Frequency: Hybridization

    Hydrocarbons such as alkanes, alkenes, and alkynes show characteristic C–H stretching absorption bands. These IR stretching frequencies depend on the hybridization of the involved carbon atom and can be explained in terms of the s character of each hybridized atomic orbital.
    Among the sp, sp2, and sp3 hybridized orbitals, sp orbitals have the maximum s character (50%). Consequently, the electrons are held more closely to the nucleus, resulting in stronger and shorter C–H bonds that stretch at a...
    IR Absorption Frequency: Delocalization01:04

    IR Absorption Frequency: Delocalization

    Electron delocalization refers to the distribution of electrons across multiple atoms within a molecule rather than being confined to a single atom or bond. This phenomenon is common in systems with conjugated bonds—structures where alternating single and double bonds allow π-electrons to move freely across the network. The movement of electrons stabilizes the molecule and can affect various chemical properties, including vibrational frequencies observed in IR spectroscopy.
    In IR spectroscopy,...
    Carrier Generation and Recombination01:22

    Carrier Generation and Recombination

    Carrier generation is the process by which electron-hole pairs (EHPs) are created within the semiconductor. In direct-bandgap semiconductors, such as gallium arsenide (GaAs), this occurs efficiently when energy absorption prompts valence electrons to leap into the conduction band, leaving behind holes.
    This process is given by the generation rate G and is efficient due to the conservation of momentum between the valence band maximum and conduction band minimum.
    Indirect generation involves an...
    IR Spectrum Peak Splitting: Symmetric vs Asymmetric Vibrations01:08

    IR Spectrum Peak Splitting: Symmetric vs Asymmetric Vibrations

    Identical bonds within a polyatomic group can stretch symmetrically (in-phase) or asymmetrically (out-of-phase). Similar to hydrogen bonding, these vibrations also influence the shape of the IR peak. Generally, asymmetric stretching frequencies are higher than symmetric stretching frequencies. For example, primary amines exhibit two distinct IR peaks between 3300–3500 cm−1 corresponding to the symmetric and asymmetric N-H stretching, while secondary amines exhibit a single stretching vibration...
    Infrared (IR) Spectroscopy: Overview01:09

    Infrared (IR) Spectroscopy: Overview

    When electromagnetic radiation passes through a material, atoms or molecules transition from a lower to a higher energy state by absorbing radiation corresponding to the energy difference between the two states. The absorption of infrared (IR) radiation causes transitions between vibrational energy levels in a molecule. Therefore, IR spectroscopy is a useful analytical tool for determining the molecular structure of molecules.
    Different compounds display unique properties due to their...
    IR Spectroscopy: Molecular Vibration Overview01:24

    IR Spectroscopy: Molecular Vibration Overview

    When Infrared (IR) radiation passes through a covalently bonded molecule, the bonds transition from lower to higher vibrational levels. The fundamental vibrational motions that result in infrared absorption can be classified as stretching or bending vibrations.
    Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...