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

Protein and Protein Structure02:15

Protein and Protein Structure

87.0K
Proteins are one of the most abundant organic molecules in living systems and have the most diverse range of functions of all macromolecules. Proteins may be structural, regulatory, contractile, or protective. They may serve in transport, storage, or membranes; or they may be toxins or enzymes. Their structures, like their functions, vary greatly. They are all, however, amino acid polymers arranged in a linear sequence.
A protein's shape is critical to its function. For example, an enzyme...
87.0K
Levels of Organization01:09

Levels of Organization

139.0K
Biological organization is the classification of biological structures, ranging from atoms at the bottom of the hierarchy to the Earth's biosphere. Each level of the hierarchy represents an increase in complexity that builds upon the previous level.
Molecules Are Composed of Atoms, and Biomolecules Are Assembled from Molecules:
The most basic levels include atoms, molecules, and biomolecules. Atoms, the smallest unit of ordinary matter, are composed of a nucleus and electrons. Molecules...
139.0K
Standard Electrode Potentials03:02

Standard Electrode Potentials

50.0K
On comparing the reactivity of silver and lead, it is observed that the two ionic species, Ag+ (aq) and Pb2+ (aq), show a difference in their redox reactivity towards copper: the silver ion undergoes spontaneous reduction, while the lead ion does not. This relative redox activity can be easily quantified in electrochemical cells by a property called cell potential. This property is commonly known as cell voltage in electrochemistry, and it is a measure of the energy which accompanies the charge...
50.0K
High-Level and Low-Level Awareness01:19

High-Level and Low-Level Awareness

631
Controlled processes in human consciousness represent high-alert mental states where individuals deliberately focus their attention on achieving specific goals. Controlled processes can be seen in situations like mastering new technology, where a person might become so absorbed that they ignore surrounding distractions. Such processes involve selective attention, requiring one to concentrate on particular elements of experience while disregarding others. These are governed by executive...
631
Leveling Effect01:29

Leveling Effect

1.4K
In acid-base chemistry, the leveling effect refers to the limitation imposed by the solvent on the strength of acids and bases in solution. When a base stronger than the solvent's conjugate base is used, it deprotonates the solvent until the base is entirely consumed, making it ineffective against weaker acids. Conversely, an acid stronger than the solvent's conjugate acid protonates the solvent until the acid is depleted, rendering it ineffective against weaker bases. Essentially, the...
1.4K
Potential Energy00:52

Potential Energy

42.4K
The energy stored by a structure and location of matter in space is called potential energy. For instance, raising a kettlebell changes its spatial location and increases its potential energy. Similarly, a stretched rubber band contains potential energy which, under certain conditions, can be converted into other forms of energy, such as kinetic energy.
Chemical bonds that form attractive forces between atoms also contain potential energy, called chemical energy. When a chemical reaction...
42.4K

You might also read

Related Articles

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

Sort by
Same author

Thermopower Probe of Fractional Quantum Hall States in Monolayer Graphene.

Physical review letters·2026
Same author

Relativistic quantum phenomena in graphene quantum dots.

Nature nanotechnology·2023
Same author

Edge channels of broken-symmetry quantum Hall states in graphene visualized by atomic force microscopy.

Nature communications·2021
Same author

Tuning single-electron charging and interactions between compressible Landau level islands in graphene.

Physical review. B·2020
Same author

Achieving μeV tunneling resolution in an in-operando scanning tunneling microscopy, atomic force microscopy, and magnetotransport system for quantum materials research.

The Review of scientific instruments·2020
Same author

Disorder induced power-law gaps in an insulator-metal Mott transition.

Proceedings of the National Academy of Sciences of the United States of America·2018

Related Experiment Video

Updated: Jan 22, 2026

Structure of HIV-1 Capsid Assemblies by Cryo-electron Microscopy and Iterative Helical Real-space Reconstruction
12:38

Structure of HIV-1 Capsid Assemblies by Cryo-electron Microscopy and Iterative Helical Real-space Reconstruction

Published on: August 9, 2011

17.8K

Helical Level Structure of Dirac Potential Wells.

Daniel Walkup1,2, Joseph A Stroscio1

  • 1Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.

Physical Review. B
|July 6, 2019
PubMed
Summary

In graphene and similar Dirac materials, a mass term resolves energy spectrum discontinuities in circular potential wells. This allows adiabatic transitions between quantum states, controlled by magnetic fields and mass, resembling a spiral staircase.

More Related Videos

Improving the Combustion Performance of a Hybrid Rocket Engine using a Novel Fuel Grain with a Nested Helical Structure
07:58

Improving the Combustion Performance of a Hybrid Rocket Engine using a Novel Fuel Grain with a Nested Helical Structure

Published on: January 18, 2021

6.5K
Helical Organization of Blood Coagulation Factor VIII on Lipid Nanotubes
12:24

Helical Organization of Blood Coagulation Factor VIII on Lipid Nanotubes

Published on: June 3, 2014

12.7K

Related Experiment Videos

Last Updated: Jan 22, 2026

Structure of HIV-1 Capsid Assemblies by Cryo-electron Microscopy and Iterative Helical Real-space Reconstruction
12:38

Structure of HIV-1 Capsid Assemblies by Cryo-electron Microscopy and Iterative Helical Real-space Reconstruction

Published on: August 9, 2011

17.8K
Improving the Combustion Performance of a Hybrid Rocket Engine using a Novel Fuel Grain with a Nested Helical Structure
07:58

Improving the Combustion Performance of a Hybrid Rocket Engine using a Novel Fuel Grain with a Nested Helical Structure

Published on: January 18, 2021

6.5K
Helical Organization of Blood Coagulation Factor VIII on Lipid Nanotubes
12:24

Helical Organization of Blood Coagulation Factor VIII on Lipid Nanotubes

Published on: June 3, 2014

12.7K

Area of Science:

  • Condensed Matter Physics
  • Quantum Mechanics
  • Materials Science

Background:

  • Graphene and massless Dirac materials exhibit Klein tunneling, hindering electron confinement.
  • Their energy spectra in circular potentials show discontinuities at critical magnetic fields (Bc).
  • Momentum-space contours possess a Berry phase of 0 or π, influencing spectral behavior.

Purpose of the Study:

  • To investigate the effect of introducing a mass term (Δ) into the Hamiltonian of circular potential wells in Dirac materials.
  • To demonstrate how a mass term bridges the energy spectrum discontinuity.
  • To explore the adiabatic connection of quantum states across critical fields and the role of Berry phase.

Main Methods:

  • Theoretical analysis of the Hamiltonian for circular potential wells in Dirac materials with an added mass term.
  • Examination of the energy spectrum as a function of magnetic field (B) and mass term (Δ).
  • Application of adiabatic evolution principles to quantum states in the B-Δ plane.

Main Results:

  • Introducing a mass term (Δ) connects states below Bc to states above Bc, with a unit change in principal quantum number.
  • The energy spectrum in the B-Δ plane forms a spiral staircase pattern.
  • Adiabatic circuits around Bc allow transitions between resonance states |n, m⟩ and |n±1, m⟩, with the sign depending on Δ and circuit direction.

Conclusions:

  • Mass terms effectively resolve spectral discontinuities in massless Dirac materials.
  • The observed spiral staircase spectrum and state transitions are explained by the evolving Berry phase.
  • This work offers a new perspective on controlling quantum states in 2D Dirac materials.