Related Experiment Video
Updated: Aug 6, 2026

Ohmic Contact Fabrication Using a Focused-ion Beam Technique and Electrical Characterization for Layer Semiconductor Nanostructures
Published on: December 5, 2015
Reversible layered/non-layered phase transition in a topological semimetal
Qingrong Liang1, Jiali Chen1, Zhaoyang Xie1
1Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing, 100081, China.
Abstract:
The essence of phase transition is symmetry breaking according to Landau's theory, which serves as a fundamental spatial metric to shape materials' structures and facilitate the discovery of emergent quantum phases. However, isocompositional phase transitions between layered and non-layered structures are typically restricted to the same bonding network due to the significant differences in surface energies and out-of-plane chemical bonds. Here, we demonstrate a reversible phase transition between layered and non-layered phases in the semimetal PtBi2, where two phases exhibit diverse structural and physical properties in terms of atomic bonding types and topological properties. Reversible resistance hysteresis loops are revealed in the electrical measurements, which originate from the layered/non-layered phase transition based on the mechanism of intralayer splitting and interlayer reconstructions. Theoretical calculations further support that the interfacial phase transition not only produces a layered/non-layered structural change, but also structure-dependent topological invariants, establishing layered/non-layered phase engineering as a platform for exploring topological and functional quantum states.
Related Concept Videos
Phase Transitions
Phase Transitions
Metal-Semiconductor Junctions
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 semiconductor's...
Phase Transitions: Sublimation and Deposition
Phase Transitions: Melting and Freezing
Phase Changes
A substance melts or freezes at a temperature called its melting point and boils or condenses at its boiling point. These temperatures depend on pressure. High pressure favors the denser form of the substance, so typically, high pressure...

