Electronic Liquid Crystal Physics of Underdoped Cuprates

Eun-Ah Kim; Michael J. Lawler

doi:10.1016/j.physc.2012.04.038

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arXiv · 1205.6408

Electronic Liquid Crystal Physics of Underdoped Cuprates

Eun-Ah Kim·Michael J. Lawler

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Abstract

Recent observations of broken symmetries have partly demystified the pseudogap phase. Here we review evidence for long-range intra-unit-cell(IUC) nematic order and its unexpectedly strong coupling to the phase of the fluctuating stripes in the pseudogap states of underdoped Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$. In particular, we focus on the analysis techniques that reveal this evidence in scanning tunneling spectroscopy data, the definition of the extracted IUC nematic order parameter, and a phenomenological theory of the coupling between the IUC nematic order and the previously reported coexisting fluctuating stripes. We also present a microscopic mechanism of IUC nematic order driven by on-site and near-neighbor repulsions. Finally we discuss open questions in the context of these results.

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Eun-Ah Kim, Michael J. Lawler. 2012-05-29. Electronic Liquid Crystal Physics of Underdoped Cuprates. https://doi.org/10.1016/j.physc.2012.04.038

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