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

Semiconductors01:22

Semiconductors

758
There is variation in the electrical conductivity of materials - metals, semiconductors, and insulators that are showcased with the help of the energy band diagrams.
Metals such as copper (Cu), zinc (Zn), or lead (Pb) have low resistivity and feature conduction bands that are either not fully occupied or overlap with the valence band, making a bandgap non-existent. This allows electrons in the highest energy levels of the valence band to easily transition to the conduction band upon gaining...
758
Types of Semiconductors01:20

Types of Semiconductors

691
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...
691
Fermi Level Dynamics01:12

Fermi Level Dynamics

298
The vacuum level denotes the energy threshold required for an electron to escape from a material surface. It is usually positioned above the conduction band of a semiconductor and acts as a benchmark for comparing electron energies within various materials.
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
298
Fermi Level01:18

Fermi Level

703
The Fermi-Dirac function is represented by an S-shaped curve indicating the probability of an energy state being occupied by an electron at a given temperature. The Fermi level is the energy level at which there is a fifty percent chance of finding an electron, and it is positioned between the lower-energy valence band and the higher-energy conduction band.
At absolute zero temperature, electrons fill all energy states up to the Fermi level, leaving upper states empty. As the temperature rises,...
703
Metal-Semiconductor Junctions01:24

Metal-Semiconductor Junctions

404
The contact of metal and semiconductor can lead to the formation of a junction with either Schottky or Ohmic behavior.
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The...
404
Energy Bands in Solids01:01

Energy Bands in Solids

984
Isolated atoms have discrete energy levels that are well described by the Bohr model. And, it quantifies the energy of an electron in a hydrogen atom as En. Higher quantum numbers 'n' yield less negative, closer electron energy levels.
 Band Formation:
When atoms are brought close together, as in a solid, these discrete energy levels begin to split due to the overlap of electron orbitals from adjacent atoms. This split occurs because of the Pauli exclusion principle, which states...
984

You might also read

Related Articles

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

Sort by
Same author

A superconducting transition edge sensor array for synchrotron soft x-ray emission spectroscopies of low-dimensional and impurity-level concentration systems.

The Review of scientific instruments·2026
Same author

Metamaterials and Fluid Flows.

Nature communications·2026
Same author

Single-cell profiling delineates the tumor microenvironment and immunological networks in patient-derived uterine leiomyosarcoma.

Frontiers in immunology·2025
Same author

Intelligent prediction of thyroid cancer in China based on GBD data and hospital electronic medical records: disease burden analysis combined with multiple machine learning models.

Frontiers in endocrinology·2025
Same author

<i>Sclerotinia</i> spp. causing root rot of <i>Panax ginseng</i> in Northeast China and its potential biocontrol by <i>Bacillus amyloliquefaciens</i> FS6.

Microbiology spectrum·2025
Same author

The effect of postoperative hypotension on surgical patients' adverse clinical outcomes: A systematic review and meta-analysis.

Journal of clinical anesthesia·2025

Related Experiment Video

Updated: Aug 6, 2025

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
10:40

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy

Published on: June 28, 2016

7.6K

Semiconductor Thermal and Electrical Properties Decoupled by Localized Phonon Resonances.

Bryan T Spann1, Joel C Weber1, Matt D Brubaker1

  • 1Physical Measurement Laboratory, National Institute of Standards and Technology (NIST), Boulder, CO, 80302, USA.

Advanced Materials (Deerfield Beach, Fla.)
|March 23, 2023
PubMed
Summary

Researchers developed a new method to improve thermoelectric materials by adding nanopillars. This innovation reduces thermal conductivity by 21% without affecting electrical properties, paving the way for efficient energy recovery and cooling.

Keywords:
gallium nitridenanophononic metamaterialsnanopillarsthermal transportthermoelectrics

More Related Videos

Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
05:39

Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform

Published on: August 2, 2019

9.7K
Fabrication and Characterization of Superconducting Resonators
10:26

Fabrication and Characterization of Superconducting Resonators

Published on: May 21, 2016

11.4K

Related Experiment Videos

Last Updated: Aug 6, 2025

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
10:40

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy

Published on: June 28, 2016

7.6K
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
05:39

Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform

Published on: August 2, 2019

9.7K
Fabrication and Characterization of Superconducting Resonators
10:26

Fabrication and Characterization of Superconducting Resonators

Published on: May 21, 2016

11.4K

Area of Science:

  • Materials Science
  • Solid-State Physics
  • Nanotechnology

Background:

  • Thermoelectric materials are crucial for energy conversion and cooling, requiring high electrical conductivity and low thermal conductivity.
  • Achieving this balance is challenging due to the interconnected nature of charge carrier and phonon scattering mechanisms.
  • Previous theories suggested nanopillars could reduce thermal conductivity without impacting electrical properties.

Purpose of the Study:

  • To experimentally demonstrate the theoretical prediction of reduced thermal conductivity using nanopillars on thermoelectric devices.
  • To investigate the impact of gallium nitride (GaN) nanopillars on silicon (Si) membranes for thermoelectric applications.
  • To achieve an unprecedented decoupling of thermal and electrical properties in semiconductors.

Main Methods:

  • Fabrication of suspended silicon membranes with GaN nanopillars.
  • Experimental measurement of thermal conductivity and power factor.
  • Lattice-dynamics calculations to understand phonon behavior and resonances.

Main Results:

  • A reduction of up to 21% in in-plane thermal conductivity was observed.
  • The power factor, a measure of electrical performance, remained unaffected.
  • Experimental results correlated with lattice-dynamics calculations, confirming the role of phonon resonances.

Conclusions:

  • The study experimentally validates that nanopillars can significantly reduce thermal conductivity in thermoelectric materials.
  • This approach successfully decouples thermal and electrical transport properties in semiconductors.
  • The findings offer a promising pathway for developing high-efficiency solid-state energy recovery and cooling technologies.