Abstract Based upon the spin wave theory, the influence of the size of a three-dimensional Heisenberg system on its thermodynamic properties was studied. It is found that the specific heat increases due to the finite size and free surface of the system. For a magnetic film with finite thickness, the interaction of spin waves was also discussed. There exist three additional scattering processes, namely, the scattering between spin waves with wave-vectors parallel to the surface of the film (two-dimensional spin wave), the scattering between two and three-dimensional waves, and the scattering between those waves with the same component in the direction along the thickness of the film. As a result, the T4 term, arising from the coupling of spin waves, in the expression of the specific heat of the system, splite into three parts proportional to T5/2,T7/2 and T4, respectively. Here T is the temperature.
Received: 18 October 1994
Accepted manuscript online:
(Quantized spin models, including quantum spin frustration)
Fund: Project supported by the National Scaling Project of Nanocrystal Materials of China.
Cite this article:
SUN JI-RONG (孙继荣), WEI YU-NIAN (魏玉年), PU FU-CHO (蒲富恪) SPECIFIC HEAT OF A HEISENBERG SYSTEM WITH FINITE SIZE 1995 Acta Physica Sinica (Overseas Edition) 4 542
Altmetric calculates a score based on the online attention an article receives. Each coloured thread in the circle represents a different type of online attention. The number in the centre is the Altmetric score. Social media and mainstream news media are the main sources that calculate the score. Reference managers such as Mendeley are also tracked but do not contribute to the score. Older articles often score higher because they have had more time to get noticed. To account for this, Altmetric has included the context data for other articles of a similar age.