We consider a regular chain of elementary quantum systems with nearest neighbor interactions and assume that the total system is in a canonical state with temperature T. We analyze under what condition the state factors into a product of canonical density matrices with respect to groups of n subsystems each, and when these groups have the same temperature T. While in classical mechanics the validity of this procedure only depends on the size of the groups n, in quantum mechanics the minimum group size nmin also depends on the temperature T! As examples, we apply our analysis to different types of Heisenberg spin chains.
|Number of pages||4|
|Journal||Journal of the Physical Society of Japan|
|Publication status||Published - 2005|
- Local temperature
- Quantum many particle systems
ASJC Scopus subject areas
- Physics and Astronomy(all)