Abstract

We employ the spinor analysis method to evaluate exact expressions of spin-spin correlation functions of the two-dimensional rectangular Ising model on a finite lattice, special process enables us to actually carry out the calculation process. We first present some exact expressions of correlation functions of the model with periodic-periodic boundary conditions on a finite lattice. The corresponding forms in the thermodynamic limit are presented, which show the short-range order. Then, we present the exact expression of the correlation function of the two farthest pair of spins in a column of the model with periodic-free boundary conditions on a finite lattice. Again, the corresponding form in the thermodynamic limit is discussed, from which the long-range order clearly emerges as the temperature decreases.

Highlights

  • Since the exact solution of the partition function in the absence of a magnetic field of the two-dimensional rectangular Ising model with periodic-periodic boundary conditions is obtained in the thermodynamic limit [1] and in finite-size systems [2], many authors have contributed to the knowledge of various aspects of this model, such as different boundary conditions, the arrangement modes of the spin lattice, surfaces, or mathematical methods, etc. [3,4,5,6,7]

  • Besides the partition function of the model, the calculations of spin-spin correlation functions are an important subject in the research of the two-dimensional Ising model

  • We present some exact expressions of spin-spin correlation functions of the two-dimensional rectangular Ising model on a finite lattice by employing the spinor analysis method [2]

Read more

Summary

Introduction

Since the exact solution of the partition function in the absence of a magnetic field of the two-dimensional rectangular Ising model with periodic-periodic boundary conditions is obtained in the thermodynamic limit [1] and in finite-size systems [2], many authors have contributed to the knowledge of various aspects of this model, such as different boundary conditions, the arrangement modes of the spin lattice, surfaces, or mathematical methods, etc. [3,4,5,6,7]. Since RSPT is irregular, the approximate method is incapable when Q is very larger By this approach we can only obtain exact expressions of correlation functions when Q is a small number, for example, that of hσ , σ1 , 2 i , hσ , σ1 , 3 i , hσ , σ1 , 4 i , · · · , etc., which belong to the short-range order. After obtaining the exact expression of σl , 1 σl , N , we discuss the properties of the expression of σl , 1 σl , N in the thermodynamic limit, from which the long-range order emerges as the temperature decreases, as shown clearly

Short-Range Order in Onsager’s Lattice
Basic Properties of the Eigenvalues and Eigenvectors of the Matrix H
E Dobtain the exact
Lγm cosh cos θm tanh
M cos θm
M 4 cos
Long Range-Order in the Model with Periodic-Free Boundary Conditions
Some Results Concerning the Partition Function Z0
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call