| 題名: | Perturbation theory about generalized self-consistent field solution |
| 作者: | Yang, C.;Kocharian, A.N.;Chiang, Y.L.;Chen, L.Y. |
| 貢獻者: | 物理學系 |
| 日期: | 2005 |
| 上傳時間: | 2009-10-30 14:43:55 (UTC+8) |
| 摘要: | A new efficient converging perturbation technique valid for arbitrary interaction strength U/t and electron concentration n is applied to study strongly correlated electrons within the repulsive Hubbard model. We test the new perturbation expansion theory in terms of interacting quasi-particles about generalized self-consistent field (GSCF) solution in an entire parameter space. The developed perturbation formalism for strong interaction and large perturbation region differs from the traditional theory on the vicinity of non-interacting electrons by incorporating systematically fluctuations of quasi-particles around self-consistent solution. Performed analytical calculations of the ground state properties in the extreme conditions of one dimensionality provide quite reasonable numerical agreement with the Bethe-ansatz results in the intermediate range of U/t and n. The results are compared with the predictions of traditional perturbation theory. |
| 關聯: | INTERNATIONAL JOURNAL OF MODERN PHYSICS B v.19 n.14 Pages: 2225-2249 |
| 顯示於類別: | [光電物理系] 期刊論文
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