set5 - Department of Physics The Ohio State University...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Department of Physics Prof. R. Bundschuh The Ohio State University Fifth Problem Set for Physics 847 (Statistical Physics II) Winter quarter 2004 Important dates: Feb 10 10:30am-12:18pm midterm exam, Mar 16 9:30am-11:18am ±nal exam Due date: Thursday, Feb 12 13. Spin correlations 8 points Consider a one-dimensional lattice with N lattice sites and assume that the i th lattice site has spin s i = ± 1. The Hamiltonian describing this lattice is H = - ε N i =1 s i s i +1 . Assume periodic boundary conditions, so s N +1 s 1 . Compute the correlation function h s 1 s 2 i . How does it behave at very high temperature and at very low temperature? 14. Spin 1 magnet 12 points Consider a lattice of N spins s i which can take values s i ∈ {- 1 , 0 , 1 } . In the absence of an external magnetic ±eld the energy of this system is given by H = - ε X { i,j } s i s j . Apply the mean ±eld approximation to this system. Denote the number of nearest neighbors of a spin by ν . a) At which temperature
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 07/17/2008 for the course PHYS 847 taught by Professor Bundschuh during the Winter '04 term at Ohio State.

Page1 / 2

set5 - Department of Physics The Ohio State University...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online