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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Magnetic field blocks two-dimensional crystallization in strongly coupled plasmas
1Institut für Theoretische Physik II: Weiche Materie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany.
Physical Review Letters
|August 27, 2013
Summary
External magnetic fields can prevent crystallization in two-dimensional plasmas. Increasing magnetic field strength exponentially slows the transition from fluid to crystal, a key finding for controlling plasma states.
Area of Science:
- Plasma Physics
- Condensed Matter Physics
- Non-equilibrium Statistical Mechanics
Background:
- Two-dimensional (2D) strongly coupled plasmas are model systems for studying phase transitions.
- Standard theories of 2D freezing do not predict a significant nucleation barrier.
- Understanding factors that influence crystallization dynamics is crucial for plasma control.
Purpose of the Study:
- To investigate the effect of external magnetic fields on the crystallization of 2D strongly coupled plasmas.
- To determine the mechanism by which magnetic fields influence the fluid-to-crystal transition.
- To explore the potential for controlling plasma metastability.
Main Methods:
- Experimental study of crystallization in a 2D strongly coupled plasma.
- Rapid cooling of a fluid plasma to induce crystallization.
- Application of external magnetic fields of varying strengths (B).
Main Results:
- External magnetic fields efficiently block crystallization in 2D strongly coupled plasmas.
- Above a critical magnetic field strength, relaxation time to equilibrium crystal increases exponentially with B.
- This blocking is attributed to hindered conversion of potential to kinetic energy.
Conclusions:
- The presence of a magnetic field introduces a nucleation barrier, opposing standard 2D freezing models.
- Magnetic fields provide a mechanism to maintain 2D plasmas in a metastable fluid state for extended periods.
- This finding offers new possibilities for controlling and manipulating plasma phase transitions.
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