Related Experiment Video
Updated: Jan 21, 2026
11:38
Combining Microfluidics and Microrheology to Determine Rheological Properties of Soft Matter during Repeated Phase Transitions
Published on: April 19, 2018
8.4K
Structural and topological phase transitions induced by strain in two-dimensional bismuth
Erika N Lima1, Tome M Schmidt2, R W Nunes3
1Universidade Federal de Mato Grosso, Departamento de Matemática, Rondonópolis, Mato Grosso, Brazil.
Summary
Strain engineering transforms 2D bismuth layers into a topological insulator. Tensile strain induces structural and electronic phase transitions in bismuthene and pentaoctite phases, revealing potential for novel topological materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Computational Physics
Background:
- Two-dimensional (2D) materials offer unique electronic properties.
- Bismuth allotropes, like bismuthene, are being explored for novel quantum phenomena.
- Understanding strain effects is crucial for tuning material properties.
Purpose of the Study:
- Investigate structural and topological electronic transitions in 2D bismuth layers under strain.
- Determine the stability of different bismuth phases under tensile strain.
- Explore the potential of 2D bismuth as a platform for topological materials.
Main Methods:
- First-principles density-functional theory (DFT) calculations.
- Analysis of structural stability and phase transformations.
- Examination of electronic band structure and topological properties.
Main Results:
- Hexagonal bismuthene is unstable under biaxial tensile strain, transforming to a pentaoctite phase.
- The pentaoctite phase transitions from a trivial to a topological insulator under strain.
- Specific strain values (5% biaxial, 6% armchair uniaxial, 5% zigzag uniaxial) trigger topological transitions.
Conclusions:
- 2D bismuth layers are a promising platform for creating topologically non-trivial materials.
- Strain engineering is an effective method to control the topological electronic properties of 2D bismuth.
- The pentaoctite phase of bismuth exhibits tunable topological insulator behavior.
More Related Videos
Related Concept Videos
02:31Phase Transitions
22.7K
Whether solid, liquid, or gas, a substance's state depends on the order and arrangement of its particles (atoms, molecules, or ions). Particles in the solid pack closely together, generally in a pattern. The particles vibrate about their fixed positions but do not move or squeeze past their neighbors. In liquids, although the particles are closely spaced, they are randomly arranged. The position of the particles are not fixed—that is, they are free to move past their neighbors to...
22.7K
02:33Phase Transitions: Sublimation and Deposition
19.8K
Some solids can transition directly into the gaseous state, bypassing the liquid state, via a process known as sublimation. At room temperature and standard pressure, a piece of dry ice (solid CO2) sublimes, appearing to gradually disappear without ever forming any liquid. Snow and ice sublimate at temperatures below the melting point of water, a slow process that may be accelerated by winds and the reduced atmospheric pressures at high altitudes. When solid iodine is warmed, the solid sublimes...
19.8K
02:39Phase Transitions: Melting and Freezing
14.7K
Heating a crystalline solid increases the average energy of its atoms, molecules, or ions, and the solid gets hotter. At some point, the added energy becomes large enough to partially overcome the forces holding the molecules or ions of the solid in their fixed positions, and the solid begins the process of transitioning to the liquid state or melting. At this point, the temperature of the solid stops rising, despite the continual input of heat, and it remains constant until all of the solid is...
14.7K
02:39Phase Transitions: Vaporization and Condensation
20.7K
The physical form of a substance changes on changing its temperature. For example, raising the temperature of a liquid causes the liquid to vaporize (convert into vapor). The process is called vaporization—a surface phenomenon. Vaporization occurs when the thermal motion of the molecules overcome the intermolecular forces, and the molecules (at the surface) escape into the gaseous state. When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules...
20.7K
01:29Three-Dimensional Analysis of Strain
597
Three-dimensional strain analysis is crucial for understanding how materials deform under stress, particularly in elastic, homogeneous materials. This method employs principal stress axes to simplify complex stress states into more understandable forms. Subjected to stress, a small cubic element within a material either expands or contracts along these axes, transforming into a rectangular parallelepiped. This transformation effectively illustrates the material's deformation. The principal...
597
02:39Phase Diagrams
49.0K
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...
49.0K