Related Experiment Video
Updated: Mar 6, 2026
10:35
Using Microwave and Macroscopic Samples of Dielectric Solids to Study the Photonic Properties of Disordered Photonic Bandgap Materials
Published on: September 26, 2014
12.8K
Novel Topological Phase with a Zero Berry Curvature
Feng Liu1, Katsunori Wakabayashi2
1Department of Nanotechnology for Sustainable Energy, School of Science and Technology, Kwansei Gakuin University, Gakuen 2-1, Sanda 669-1337, Japan.
Physical Review Letters
|March 4, 2017
Summary
We introduce a novel two-dimensional lattice model with a topological phase driven by Berry connection, not curvature. This model reveals fractional wave polarization and degenerated edge states, advancing topological physics research.
Area of Science:
- Condensed Matter Physics
- Topological Materials
- Quantum Mechanics
Background:
- Topological phases are typically characterized by Berry curvature.
- Understanding novel mechanisms for topological phases is crucial for materials science.
Purpose of the Study:
- To present a two-dimensional (2D) lattice model exhibiting a topological phase.
- To explore the role of Berry connection in achieving nontrivial topology.
- To investigate the resulting physical phenomena, such as wave polarization and edge states.
Main Methods:
- Development of a 2D lattice model.
- Analysis of the Berry connection and its integration over momentum space (2D Zak phase).
- Characterization of edge states and their properties.
Main Results:
- The model exhibits a topological phase without relying on Berry curvature.
- The Berry connection is identified as the key element for topological nontriviality.
- Fractional wave polarization in each direction was observed.
- Degenerated edge states with opposite parities were manifested.
Conclusions:
- A new route to realizing topological phases using Berry connection has been demonstrated.
- The findings offer insights into novel topological phenomena and potential applications in materials science.
- The study highlights the importance of Berry connection in topological phase transitions.
Related Concept Videos
01:27Gauss's Law: Planar Symmetry
9.8K
A planar symmetry of charge density is obtained when charges are uniformly spread over a large flat surface. In planar symmetry, all points in a plane parallel to the plane of charge are identical with respect to the charges. Suppose the plane of the charge distribution is the xy-plane, and the electric field at a space point P with coordinates (x, y, z) is to be determined. Since the charge density is the same at all (x, y) - coordinates in the z = 0 plane, by symmetry, the electric field at P...
9.8K
01:18Mohr's Circle for Plane Strain
1.3K
Mohr's circle is a crucial graphical method used to analyze plane strain by plotting strain on a set of cartesian coordinates, where the abscissa is normal strain ∈ and the ordinate is shear strain γ. Similarly to Mohr’s circle for plane stress, two points X and Y are plotted. Their coordinates are (∈x, -γXY) and (∈Y, γXY), respectively.
Mohr's circle visually represents the strain states under various conditions, which is essential for...
Mohr's circle visually represents the strain states under various conditions, which is essential for...
1.3K
01:28Phase Diagrams of Ternary Systems
14
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...
14
01:24Phase Diagram
46
A phase diagram is a graphical representation of the physical states of a substance under different conditions of temperature and pressure. It shows the boundaries between solid, liquid, and gas phases and the conditions at which these phases coexist in equilibrium. An area in a phase diagram represents a single phase, whereas lines or phase boundaries represent the equilibrium between two phases.In the phase diagram of water, the boundary line between the solid and liquid states illustrates...
46
01:19Phase Diagram
7.1K
The phase of a given substance depends on the pressure and temperature. Thus, plots of pressure versus temperature showing the phase in each region provide considerable insights into the thermal properties of substances. Such plots are known as phase diagrams. For instance, in the phase diagram for water (Figure 1), the solid curve boundaries between the phases indicate phase transitions (i.e., temperatures and pressures at which the phases coexist).
7.1K
02:39Phase Diagrams
51.0K
A phase diagram combines plots of pressure versus temperature for the liquid-gas, solid-liquid, and solid-gas phase-transition equilibria of a substance. These diagrams indicate the physical states that exist under specific conditions of pressure and temperature and also provide the pressure dependence of the phase-transition temperatures (melting points, sublimation points, boiling points). Regions or areas labeled solid, liquid, and gas represent single phases, while lines or curves represent...
51.0K