Local density of states of a quarter-filled one-dimensional Mott insulator with a boundary
Local density of states of a quarter-filled one-dimensional Mott insulator with a boundary
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具有边界的四分之一填充一维莫特绝缘体的局部态密度
DOI：
10.1103/physrevb.84.045122
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发表时间：
2011
影响因子：
3.7
通讯作者：
D. Schuricht
中科院分区：
文献类型：
--
作者：
D. Schuricht
研究了四分之一填充的一维莫特绝缘子的低能极限。我们解析地确定了存在强杂质势的状态的局部密度，这是由边界模拟的。为此，我们采用场论方法计算格林函数。局部态密度的傅里叶变换显示了杂质处自旋密度波的钉住特征以及电荷间隙以上频率处的几个色散特征。这些特征可以解释为传播自旋和电荷自由度。它们的相对强度可以归因于具有相等动量的电荷激发的“准费米子”行为。此外，我们还讨论了局限于杂质的束缚态的影响。最后，我们概述了各种一维系统的局部态密度，并讨论了扫描隧道显微镜实验的意义。
We study the low-energy limit of a quarter-filled one-dimensional Mott insulator. We analytically determine the local density of states in the presence of a strong impurity potential, which is modeled by a boundary. To this end we calculate the Green function using field theoretical methods. The Fourier transform of the local density of states shows signatures of a pinning of the spin-density wave at the impurity as well as several dispersing features at frequencies above the charge gap. These features can be interpreted as propagating spin and charge degrees of freedom. Their relative strength can be attributed to the "quasi-fermionic" behavior of charge excitations with equal momenta. Furthermore, we discuss the effect of bound states localized at the impurity. Finally, we give an overview of the local density of states in various one-dimensional systems and discuss implications for scanning tunneling microscopy experiments.