Structural transitions in interacting lattice systems

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Bétermin, Laurent, Šamaj, Ladislav, Travěnec, Igor
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916962101100544
author Bétermin, Laurent
Šamaj, Ladislav
Travěnec, Igor
author_facet Bétermin, Laurent
Šamaj, Ladislav
Travěnec, Igor
contents We consider two-dimensional systems of point particles located on rectangular lattices and interacting via pairwise potentials. The goal of this paper is to investigate the phase transitions (and their nature) at fixed density for the minimal energy of such systems. The 2D rectangle lattices we consider have an elementary cell of sides $a$ and $b$, the aspect ratio is defined as $Δ=b/a$ and the inverse particle density $A = a b$; therefore, the ``symmetric'' state with $Δ=1$ corresponds to the square lattice and the ``non-symmetric'' state to the rectangular lattice with $Δ\ne 1$. For certain types of the interaction potential, by changing continuously the particle density, such lattice systems undertake at a specific value of the (inverse) particle density $A^*$ a structural transition from the symmetric to the non-symmetric state. The structural transition can be either of first order ($Δ$ unstick from its symmetric value $Δ=1$ discontinuously) or of second order ($Δ$ unstick from $Δ=1$ continuously); the first and second-order phase transitions are separated by the so-called tricritical point. We develop a general theory on how to determine the exact values of the transition densities and the location of the tricritical point. The general theory is applied to the double Yukawa and Yukawa-Coulomb potentials.
format Preprint
id arxiv_https___arxiv_org_abs_2312_01395
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Structural transitions in interacting lattice systems
Bétermin, Laurent
Šamaj, Ladislav
Travěnec, Igor
Mathematical Physics
Classical Analysis and ODEs
74G65, 74N05, 82B26
We consider two-dimensional systems of point particles located on rectangular lattices and interacting via pairwise potentials. The goal of this paper is to investigate the phase transitions (and their nature) at fixed density for the minimal energy of such systems. The 2D rectangle lattices we consider have an elementary cell of sides $a$ and $b$, the aspect ratio is defined as $Δ=b/a$ and the inverse particle density $A = a b$; therefore, the ``symmetric'' state with $Δ=1$ corresponds to the square lattice and the ``non-symmetric'' state to the rectangular lattice with $Δ\ne 1$. For certain types of the interaction potential, by changing continuously the particle density, such lattice systems undertake at a specific value of the (inverse) particle density $A^*$ a structural transition from the symmetric to the non-symmetric state. The structural transition can be either of first order ($Δ$ unstick from its symmetric value $Δ=1$ discontinuously) or of second order ($Δ$ unstick from $Δ=1$ continuously); the first and second-order phase transitions are separated by the so-called tricritical point. We develop a general theory on how to determine the exact values of the transition densities and the location of the tricritical point. The general theory is applied to the double Yukawa and Yukawa-Coulomb potentials.
title Structural transitions in interacting lattice systems
topic Mathematical Physics
Classical Analysis and ODEs
74G65, 74N05, 82B26
url https://arxiv.org/abs/2312.01395