Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Semiconductors

Semiconductors

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...

Metal-Semiconductor Junctions

Metal-Semiconductor Junctions

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...

Band Theory

Band Theory

When two or more atoms come together to form a molecule, their atomic orbitals combine and molecular orbitals of distinct energies result. In a solid, there are a large number of atoms, and therefore a large number of atomic orbitals that may be combined into molecular orbitals. These groups of molecular orbitals are so closely placed together to form continuous regions of energies, known as the bands.
The energy difference between these bands is known as the band gap.
Conductor, Semiconductor,...

Carrier Transport

Carrier Transport

The generation of electrical current in semiconductors is fundamentally driven by two mechanisms: drift and diffusion. These processes are essential for the functionality and performance of semiconductor-based devices.
Drift Current:
The drift of charge carriers is started by an external electric field (E). Charged particles, such as electrons and holes, experience an acceleration between collisions with lattice atoms. For electrons, this results in a drift velocity (vd) given by:

Fermi Level Dynamics

Fermi Level Dynamics

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...

Valence Bond Theory

Valence Bond Theory

Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...

You might also read

Related Articles

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

Sort by

Same author

Glass-like anomalies and unconventional thermoelectric transport in chimney ladder crystals.

Nature communications·2026

Same author

Phase-selective Floquet engineering in a charge density wave material.

Proceedings of the National Academy of Sciences of the United States of America·2026

Same author

Intrinsic Layer Polarization and Multi-flatband Transport in Non-centrosymmetric Mixed-Stacked Multilayer Graphene.

Nano letters·2026

Same author

Occupation Dynamics of Floquet-Volkov States and Spectral Sum Rule.

Nano letters·2026

Same author

In twisted graphene, some electrons are heavier than others.

Nature·2026

Same author

Observation of Floquet-induced gap in graphene.

Nature materials·2026

Search research articles

Related Experiment Video

Updated: Dec 21, 2025

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

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

Published on: August 2, 2019

Interlayer quantum transport in Dirac semimetal BaGa₂.

Sheng Xu¹, Changhua Bao², Peng-Jie Guo¹

¹Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials & Micro-nano Devices, Renmin University of China, Beijing, 100872, P. R. China.

Nature Communications

|May 14, 2020

Summary

Topological semimetals like BaGa2 exhibit negative interlayer magnetoresistance due to Dirac fermion tunneling. This phenomenon, observed near the quantum limit, is sensitive to magnetic field orientation.

More Related Videos

Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots

Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots

Published on: November 1, 2013

Electric-field Control of Electronic States in WS2 Nanodevices by Electrolyte Gating

Electric-field Control of Electronic States in WS2 Nanodevices by Electrolyte Gating

Published on: April 12, 2018

Related Experiment Videos

Last Updated: Dec 21, 2025

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

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

Published on: August 2, 2019

Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots

Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots

Published on: November 1, 2013

Electric-field Control of Electronic States in WS2 Nanodevices by Electrolyte Gating

Electric-field Control of Electronic States in WS2 Nanodevices by Electrolyte Gating

Published on: April 12, 2018

Area of Science:

Condensed Matter Physics
Materials Science
Quantum Materials

Background:

Topological semimetals feature band crossings at the Fermi level (E_F).
Multilayered Dirac fermion systems show field-dependent interlayer tunneling conductivity.
BaGa₂ is a multilayered Dirac semimetal with a quasi-2D Dirac cone at E_F.

Purpose of the Study:

Investigate interlayer transport properties of BaGa₂.
Study the quantum limit phenomena in multilayered Dirac semimetals.
Explore the role of Dirac fermion tunneling in interlayer conductivity.

Main Methods:

Experimental measurement of interlayer resistivity in BaGa₂ under varying magnetic fields and angles.
Theoretical modeling of Dirac fermion tunneling between Landau levels.
Analysis of angle- and field-dependent magnetoresistance.

Main Results:

Observed negative interlayer magnetoresistance in BaGa₂ attributed to Dirac fermion tunneling.
Interlayer resistivity ρ_zz(θ) increases with field deviation from the c-axis, peaking at perpendicular fields.
Unusual interlayer transport properties consistent with tunneling between zeroth Landau levels (LLs).

Conclusions:

BaGa₂ serves as a platform to study quantum limit transport in Dirac semimetals.
The observed negative magnetoresistance is explained by Dirac fermion tunneling in the quantum limit.
Angle-dependent interlayer resistivity provides insights into quantum phenomena in multilayered systems.