Related Experiment Video
Updated: Apr 7, 2026
09:00
Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
10.7K
Interacting Surface States of Three-Dimensional Topological Insulators
Titus Neupert1, Stephan Rachel2, Ronny Thomale3
1Princeton Center for Theoretical Science, Princeton University, Princeton, New Jersey 08544, USA.
Physical Review Letters
|July 17, 2015
Summary
We numerically investigated strong topological insulators with electron-electron interactions. We found superconducting and anomalous Hall phases, along with unique boundary modes, offering insights into topological surface states.
Area of Science:
- Condensed Matter Physics
- Topological Materials Science
- Quantum Phenomena
Background:
- Strong topological insulators exhibit unique surface states protected by time-reversal symmetry.
- Electron-electron interactions can significantly alter the properties of topological surface states.
- Understanding these interactions is crucial for realizing novel quantum phenomena.
Purpose of the Study:
- To numerically investigate the impact of strong electron-electron interactions on the surface states of a strong topological insulator.
- To explore the emergence of exotic phases and boundary modes in a spherical topological insulator model.
- To provide a framework for stabilizing topologically ordered surface terminations.
Main Methods:
- Numerical investigation of a spherical topological insulator geometry.
- Mapping the single-particle problem to Landau orbitals with a central magnetic monopole.
- Assuming density-density contact interactions (attractive and repulsive).
Main Results:
- Identification of superconducting and anomalous (quantum) Hall phases for attractive and repulsive interactions, respectively.
- Discovery of chiral fermion and chiral Majorana fermion boundary modes between different phases.
- Demonstration of a spherical geometry suitable for finite-size analysis of surface states.
Conclusions:
- Electron-electron interactions drive rich phase transitions in topological insulator surface states.
- The proposed model system is well-suited for studying topologically ordered surface terminations.
- Tailored surface interactions could microscopically stabilize desired topological phases.
Related Concept Videos
01:16Equipotential Surfaces and Conductors
4.8K
For a conductor in which all charges are at rest, the conductor's surface is equipotential. The electric field is always perpendicular to equipotential surfaces. Therefore, in a conductor with static charges, the electric field just outside the conductor is always perpendicular to the conductor's surface. Any tangential component of the electric field will cause charges to move inside the conductor, which will violate the electrostatic nature of the system. In an electrostatic...
4.8K
01:27Electrostatic 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....
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
01:26Electric Field at the Surface of a Conductor
5.8K
Consider a conductor in electrostatic equilibrium. The net electric field inside a conductor vanishes, and extra charges on the conductor reside on its outer surface, regardless of where they originate.
In the 19th century, Michael Faraday conducted the famous ice pail experiment to prove that the charges always reside on the surface of a conductor. The experimental set-up consists of a conducting uncharged container mounted on an insulating stand. The outer surface of the container is...
In the 19th century, Michael Faraday conducted the famous ice pail experiment to prove that the charges always reside on the surface of a conductor. The experimental set-up consists of a conducting uncharged container mounted on an insulating stand. The outer surface of the container is...
5.8K
01:28Phase Diagrams of Ternary Systems
99
Consider a ternary system, which is composed of three components: water (W), ethanoic acid (E), and trichloromethane (T). Here, Ethanoic acid (E) is fully miscible with both water (W) and trichloromethane (T), meaning it can mix entirely with either of them. However, water and trichloromethane have partial miscibility, meaning they can only mix to a certain extent, beyond which two separate phases will form.The phase diagram of a ternary system is represented as an equilateral triangle, where...
99
01:16Surface Tension and Surface Energy
3.6K
When a paint brush is immersed in water, the bristles wave freely inside the water. When it is taken out, the bristles stick together. The reason behind this effect is surface tension.
Consider a beaker filled with liquid. The bulk molecules in the liquid experience equal attractive forces on all sides with the surrounding molecules. However, the surface molecules experience a net attractive force downward due to the bulk molecules. The surface of the liquid behaves like a stretched membrane,...
Consider a beaker filled with liquid. The bulk molecules in the liquid experience equal attractive forces on all sides with the surrounding molecules. However, the surface molecules experience a net attractive force downward due to the bulk molecules. The surface of the liquid behaves like a stretched membrane,...
3.6K
02:42Valence Bond Theory
11.7K
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...
11.7K