The Free Energy and the Scaling Function of the Ferromagnetic Heisenberg Chain in a Magnetic Field
Abstract
A nonlinear susceptibilities (the third derivative of a magnetization mS by a magnetic field h) of the S=1/2 ferromagnetic Heisenberg chain and the classical Heisenberg chain are calculated at low temperatures T. In both chains the nonlinear susceptibilities diverge as T-6 and a linear susceptibilities diverge as T-2. The arbitrary spin S Heisenberg ferromagnet [H =∑Ni=1 {-JSiSi+1-(h/S)Siz},(J>0)] has a scaling relation between mS, h and T: mS(T, h)=F(S2Jh/T2). The scaling function F(x)=(2x/3)-(44x3/135)+ O(x5) is common to all values of spin S.
- Publication:
-
Journal of the Physical Society of Japan
- Pub Date:
- July 1994
- DOI:
- 10.1143/JPSJ.63.2563
- arXiv:
- arXiv:cond-mat/9401074
- Bibcode:
- 1994JPSJ...63.2563N
- Keywords:
-
- Condensed Matter
- E-Print:
- 16 pages (revtex 2.0) + 6 PS figures upon request