Numerical Solution of the spin-1/2 Heisenberg Antiferromagnetic Chains Using a Projector Method |
| |
Authors: | Gang SUN |
| |
Institution: | Institute of Physics, Academia Sinica, P. O. Box 603, Beijing 100080, China |
| |
Abstract: | An efficient projector method is proposed to calculate the energy gap between the ground,state and the first excited state of the spin-1/2 Heisenberg antiferromagnetic chains. We exactly computed the two lowest-lying energies for the magnetization Stz= 0 and the lowestlying energy for Stz=±1 on chains up to 16 spins. The lowest-lying energy stat6 for Stz= 0 is a singlet ground state. The second lowest-lying energy state for Stz= 0 and the lowestlying energy states for Stz=±1 are triplet degenerate, which are the first excited energy states. We also imposed the Monte Carlo technique to estimate the lowest-lying energies for both Stz= 0 and 1 on longer chains up to 32 spins. We found that the singlet-triplet energy gap trends to zero as N→∞. |
| |
Keywords: | |
|
| 点击此处可从《理论物理通讯》浏览原始摘要信息 |
| 点击此处可从《理论物理通讯》下载免费的PDF全文 |
|