Self-consistent three-pole approximation study of the spin dynamics in two-dimensional antiferromagnetic Heisenberg paramagnets
- Department of Physics, Nanjing University, Nanjing 210093 (China)
- Chinese Center of Advanced Science and Technology (World Laboratory), Beijing 100080 (China)
The dynamics of spin-1/2 two-dimensional quantum Heisenberg antiferromagnets are reexamined in the framework of a self-consistent correlation theory based on the three-pole approximation of the relaxation function. The self-consistency is imposed between the static and dynamic variables, which dramatically changes the picture of the spin dynamics by broadening the quantum critical (QC) region (0.2{ital J}{lt}{ital T}{lt}{ital J}) and narrowing the renormalized classical (RC) region ({ital T}{lt}0.1{ital J}), resulting in a small spin stiffness as required by other theories. As an application of the theory, the calculated nuclear relaxation rates of 1/{ital T}{sub 1} and 1/{ital T}{sub 2{ital G}} in La{sub 2}CuO{sub 4}, without any adjustable parameters, agree well with the recent measurements in the whole temperature scale that covers both QC and RC regimes.
- OSTI ID:
- 76408
- Journal Information:
- Physical Review, B: Condensed Matter, Vol. 52, Issue 1; Other Information: PBD: 1 Jul 1995
- Country of Publication:
- United States
- Language:
- English
Similar Records
Theory of two-dimensional quantum Heisenberg antiferromagnets with a nearly critical ground state
Scaling regimes, crossovers, and lattice corrections in two-dimensional Heisenberg antiferromagnets