User Comments on STP XY Model Program (2)
Possible error in the program.
Author: Fernando Falo
Posted: March 14, 2013 at 7:06AM
Hi, I am doing the questions of the STP XY model program and I have problems with the susceptibility calculation. I think that this magnitude is not properly calculated. As usual it should be calculated using the fluctuations of magnetization susc =(  **2)/T. From my test, I think the code is dividing by T**2 instead of T and not substracting **2. Although theory says that = 0 for any temperature this is not true for simulations in a finite system. I think one can get better results substracting <M>**2.
thanks for your attention and best regards
Fernando Falo Associate professor of condensed matter physics University of Zaragoza (spain)
Re: Possible error in the program.
Author: Wolfgang
Posted: Mar 20, 2013 at 8:50PM
Dear Fernando 
You are correct. The getSusceptibility was not correct and has been changed to divide by T and to subtract **2. Thank you for pointing out the error.
Wolfgang
