Electronic liquid crystal state in the high-temperature superconductor YBCO(6.45)

TL;DR

This study reveals an electronic nematic phase in underdoped YBCO superconductor, showing a one-dimensional spin modulation and resistivity anisotropy, indicating coexistence of liquid crystal-like order with high-temperature superconductivity.

Contribution

It demonstrates the spontaneous emergence of a nematic electronic phase in YBCO, linking spin fluctuations to liquid crystal behavior in high-temperature superconductors.

Findings

Incommensurate spin modulation appears below ~150 K.

Resistivity anisotropy correlates with spin modulation.

Nematic order coexists with superconductivity in underdoped YBCO.

Abstract

Electronic phases with symmetry properties matching those of conventional liquid crystals have recently been discovered in transport experiments on semiconductor heterostructures and metal oxides at milli-Kelvin temperatures. We report the spontaneous onset of a onedimensional, incommensurate modulation of the spin system in the high-temperature superconductor YBa2Cu3O6.45 upon cooling below ~150 K, while static magnetic order is absent above 2 K. The evolution of this modulation with temperature and doping parallels that of the in-plane anisotropy of the resistivity, indicating an electronic nematic phase that is stable over a wide temperature range. The results suggest that soft spin fluctuations are a microscopic route towards electronic liquid crystals, and nematic order can coexist with high-temperature superconductivity in underdoped cuprates.