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arXiv · 0904.3114

Quasiparticle Interference in STM As a Function of Temperature: Signatures of Coherence

Dan Wulin·Yan He·Chih-Chun Chien·Dirk K. Morr·K. Levin
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Abstract

In this paper we explore the behavior of the quasi-particle interference pattern (QPI) of scanning tunneling microscopy as a function of temperature, $T$. After insuring a minimal consistency with photoemission, we find that the QPI pattern is profoundly sensitive to quasi-particle coherence and that it manifests two energy gap scales. The nearly dispersionless QPI pattern above $T_c$ is consistent with data on moderately underdoped cuprates. To illustrate the important two energy scale physics we present predictions of the QPI--inferred energy gaps as a function of $T$ for future experiments on moderately underdoped cuprates.

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Dan Wulin, Yan He, Chih-Chun Chien, Dirk K. Morr, K. Levin. 2009-07-02. Quasiparticle Interference in STM As a Function of Temperature: Signatures of Coherence. https://doi.org/10.1103/physrevb.80.134504

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