Researchers of the University of Barcelona discover a new mechanism for the creation of metastable estates

The system, designed by the UB researchers, allows forming a metastable estate directly and simultaneously to the creation of the final stable estate.
The system, designed by the UB researchers, allows forming a metastable estate directly and simultaneously to the creation of the final stable estate.
Research
(26/10/2016)

A team from the Department of Condensed Matter Physics formed by the researchers Ricard Alert, Pietro Tierno and Jaume Casademunt published in the journal Nature Communications -a study in which they describe a new mechanism to form metastable estates simultaneously to the formation of stable estates.

The system, designed by the UB researchers, allows forming a metastable estate directly and simultaneously to the creation of the final stable estate.
The system, designed by the UB researchers, allows forming a metastable estate directly and simultaneously to the creation of the final stable estate.
Research
26/10/2016

A team from the Department of Condensed Matter Physics formed by the researchers Ricard Alert, Pietro Tierno and Jaume Casademunt published in the journal Nature Communications -a study in which they describe a new mechanism to form metastable estates simultaneously to the formation of stable estates.

Metastable estates are the ones that have a fragile stability and therefore have shorter life periods. The most known example is water, which, in some conditions can be kept in liquid state below 0ºC (over-frozen), despite its stable state at these temperatures is solid (ice). This phenomenon happens because when the solidification process starts, a certain energy is needed, and getting this energy requires some time during which the system is kept in this metastable estate. The process in which solidification starts covering the energetic barrier is called nucleation.

So far, the only way to spontaneously form a metastable estate was out of another metastable estate, after covering the energetic barrier. But this team of the University of Barcelona discovered how to create a new metastable estate without having to go through any energetic barrier. The study shows how, in the system of magnetic colloid crystals design by the UB researchers, a metastable estate is formed directly and simultaneously to the formation of a final stable estate, through a process called spinodal decomposition. In waterʼs analogy, it would be like if a certain ice crystal structure formed a different solid structure from the one in frozen liquid water (despite the analogy, this process is not possible in water).

The researchers have studied the transition between two different structures of this colloid crystal structures when the magnetic field changes and they found that they produce several unexpected phenomena over the course of this transition. According to Ricard Alert, first author of the article, “our results open a new scene in the stage transition field, in which we predict a series of phenomena that were not expected in the classic theory”.

 

Reference to the article:

R. Alert, P. Tierno i J. Casademunt. «Formation of metastable phases by spinodal decomposition». Nature Communications, October 2016. DOI: 10.1038/ncomms13067