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arXiv 1303.2657cond-mat.str-el
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二维无限U Hubbard模型的电子能谱特性

Electronic spectral properties of the two-dimensional infinite-U Hubbard model

University of California, Santa Cruz(加州大学圣克鲁兹分校);Georgetown University(乔治城大学);The Pennsylvania State University(宾夕法尼亚州立大学)

Ehsan Khatami, Daniel Hansen, Edward Perepelitsky, Marcos Rigol, B. Sriram Shastry

AI总结:

本文利用ECFL理论和强耦合级数展开方法研究无限U Hubbard模型的电子能谱特性,发现修改后的第一矩能准确描述强相关区域的准粒子峰位置。

摘要:

强相关费米液体(ECFL)理论和强耦合级数展开方法被用于计算无限U Hubbard模型的电子能谱函数的矩。这两种互补方法在低密度区域和高温到中温区域的结果非常一致。我们发现,一个修改后的第一矩,它低估了占据态的贡献,但可以通过时间依赖的格林函数在级数中获得,最好地描述了强相关区域中的准粒子峰位置。通过ECFL结果在低温下的检验,显示能谱函数主要偏向于占据态。

英文摘要:

A strong-coupling series expansion for the Green's function and the extremely-correlated Fermi liquid (ECFL) theory are used to calculate the moments of the electronic spectral functions of the infinite-U Hubbard model. Results from these two complementary methods agree very well at both, low densities, where the ECFL solution is the most accurate, and at high to intermediate temperatures, where the series converge. We find that a modified first moment, which underestimates the contributions from the occupied states and is accessible in the series through the time-dependent Green's function, best describes the quasiparticle peak location in the strongly-correlated regime. This is examined by the ECFL results at low temperatures, where it is shown that the spectral function is largely skewed towards the occupied states.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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