Related Experiment Video
Updated: Jul 23, 2025
10:35
Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
8.8K
Inverse Design of Light Manipulating Structural Phase Transition in Solids
Wenhao Liu1,2, Haowen Liu1,2, Zhi Wang1
1State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.
The Journal of Physical Chemistry Letters
|July 18, 2023
Summary
Researchers reveal how light-excited electrons drive ultrafast structural phase transitions in materials. They propose a method for precisely controlling these transitions using orbital-selective photoexcitation, enabling tailored material properties.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Ultrafast Spectroscopy
Background:
- Photoinduced structural phase transitions are crucial for material properties.
- Understanding the ultrafast dynamics of these transitions is key to controlling them.
- Existing models often lack detailed insights into the electronic origins of these changes.
Purpose of the Study:
- To provide a comprehensive overview of recent advances in ultrafast processes driving structural phase transitions.
- To propose a novel strategy for precise manipulation of photoinduced structural transitions.
- To elucidate the electronic-orbital-selective nature of laser-induced structural changes.
Main Methods:
- Analysis of recent experimental and theoretical studies on ultrafast structural dynamics.
- Theoretical modeling of photoexcited carrier dynamics and resulting atomic forces.
- Proposal of an inverse design protocol based on orbital-selective photoexcitation.
Main Results:
- Photoexcited carriers occupying specific electronic states (bonding/antibonding) induce atomic driving forces.
- These forces lead to bond stretching/shortening and collective atomic motions, causing structural transitions.
- Examples include phase transitions in IrTe2, VO2, and nonthermal melting in Si, explained by electronic state occupation.
Conclusions:
- Laser-induced structural transitions are governed by the occupation of specific electronic orbitals.
- Orbital-selective photoexcitation offers a precise method for controlling structural phase transitions.
- This approach enables the inverse design of materials with desired dynamical properties.
Related Concept Videos
02:31Phase Transitions
19.2K
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...
19.2K
02:33Phase Transitions: Sublimation and Deposition
17.2K
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...
17.2K
01:19Phase Changes
4.4K
Phase transitions play an important theoretical and practical role in the study of heat flow. In melting or fusion, a solid turns into a liquid; the opposite process is freezing. In evaporation, a liquid turns into a gas; the opposite process is condensation.
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...
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...
4.4K
02:39Phase Transitions: Melting and Freezing
12.5K
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...
12.5K
01:19Phase Diagram
5.9K
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).
5.9K