UB researchers discover a new type of phase transition

The energy of a system as the height of the relief of a mountain landscape, the equilibrium state would correspond to standing on the valley.
The energy of a system as the height of the relief of a mountain landscape, the equilibrium state would correspond to standing on the valley.
Research
(01/12/2014)

We are surrounded by many everyday phenomena in which a substance changes its physical state. For example, the boiling of water in a pan, where liquid water transforms into vapour, or the melting of an ice cube in a glass of whisky, where water goes from the solid to the liquid phase. They are known in Physics as first-order phase transitions.

 

The energy of a system as the height of the relief of a mountain landscape, the equilibrium state would correspond to standing on the valley.
The energy of a system as the height of the relief of a mountain landscape, the equilibrium state would correspond to standing on the valley.
Research
01/12/2014

We are surrounded by many everyday phenomena in which a substance changes its physical state. For example, the boiling of water in a pan, where liquid water transforms into vapour, or the melting of an ice cube in a glass of whisky, where water goes from the solid to the liquid phase. They are known in Physics as first-order phase transitions.

 

Researchers from the Faculty of Physics of the University of Barcelona (UB) have discovered a new scenario of first-order phase transitions. The equilibrium state of a substance is always that of minimum energy. “If one imagines the energy of a system as the height of the relief of a mountain landscape, the equilibrium state would correspond to standing on the valley”, explains Ricard Alert, first author of the study and researcher in the Department of Structure and Constituents of Matter of the UB.

A phase transition usually takes place when a nearby valley gets deeper and one can move to it. The scientific paper, published in the journal Physical Review Letters, “shows that a first-order phase transition can also occur because of a complete inversion of the energy landscape, as if the mountainsʼ relief suddenly became that of its reflection on a lake”, says Jaume Casademunt, researcher at the former department.

Theory, simulations, and experiments on a crystal of magnetic particles are used to demonstrate the non-conventional features of the so-called ʻlandscape-inversion phase transitionʼ, thus adding new ingredients to the traditional field of phase transitions. “This new scenario of first-order phase transitions that occurs via a complete inversion of the energy landscape, featuring nonconventional properties that allow for example tuning of crystal symmetry or control some dynamical properties”, concludes Pietro Tierno, member of the research group.

R. Alert, J. Casademunt, P. Tierno. “Landscape-Inversion Phase Transition in Dipolar Colloids: Tuning the Structure and Dynamics of 2D Crystals”. Physical Review Letters, 4 November 2014. DOI: 10.1103/PhysRevLett.113.198301