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Observation of an electronic order along [110] direction in FeSe.

ABSTRACT: Multiple ordered states have been observed in unconventional superconductors. Here, we apply scanning tunneling microscopy to probe the intrinsic ordered states in FeSe, the structurally simplest iron-based superconductor. Besides the well-known nematic order along [100] direction, we observe a checkerboard charge order in the iron lattice, which we name a [110] electronic order in FeSe. The [110] electronic order is robust at 77 K, accompanied with the rather weak [100] nematic order. At 4.5 K, The [100] nematic order is enhanced, while the [110] electronic order forms domains with reduced correlation length. In addition, the collective [110] order is gaped around [-40, 40] meV at 4.5 K. The observation of this exotic electronic order may shed new light on the origin of the ordered states in FeSe.

SUBMITTER: Bu K

PROVIDER: S-EPMC7925548 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Observation of an electronic order along [110] direction in FeSe.

Bu Kunliang K Zhang Wenhao W Fei Ying Y Zheng Yuan Y Ai Fangzhou F Wu Zongxiu Z Wang Qisi Q Wo Hongliang H Zhao Jun J Yin Yi Y

Nature communications 20210302 1

Multiple ordered states have been observed in unconventional superconductors. Here, we apply scanning tunneling microscopy to probe the intrinsic ordered states in FeSe, the structurally simplest iron-based superconductor. Besides the well-known nematic order along [100] direction, we observe a checkerboard charge order in the iron lattice, which we name a [110] electronic order in FeSe. The [110] electronic order is robust at 77 K, accompanied with the rather weak [100] nematic order. At 4.5 K, ...[more]

PMID: 33654059

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