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Design and Differentiation of Quantum States at Subnanometer Scale in La₂CuO₄-Sr₂CuO_4-δ Superlattices.

ABSTRACT: We present a study on the properties of superlattices made of ultrathin Sr₂CuO_4-δ layers sandwiched between La₂CuO₄ layers beyond the antiferromagnetic insulating nature of the individual layers of choice. Using molecular beam epitaxy, we synthesized these superlattices and observed superconductivity and metallicity at the interfaces. We probed the hole distribution to determine the discernible quantum states and found that the high-quality epitaxy, combined with mapping the electronic fine structure by electron energy-loss spectroscopy, allowed for the differentiation of insulating, metallic, and superconducting layers at the atomic-column scale. Our results demonstrate the possibility of exploring specific electronic properties at the subnanometer scale and highlight the potential of utilizing metastable Sr₂CuO_4-δ slabs.

SUBMITTER: Bonmassar N

PROVIDER: S-EPMC10311586 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

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Design and Differentiation of Quantum States at Subnanometer Scale in La2CuO4-Sr2CuO4-δ Superlattices.

Bonmassar Nicolas N Christiani Georg G Salzberger Ute U Wang Yi Y Logvenov Gennady G Suyolcu Y Eren YE van Aken Peter A PA

ACS nano 20230601 12

We present a study on the properties of superlattices made of ultrathin Sr2CuO4-δ layers sandwiched between La2CuO4 layers beyond the antiferromagnetic insulating nature of the individual layers of choice. Using molecular beam epitaxy, we synthesized these superlattices and observed superconductivity and metallicity at the interfaces. We probed the hole distribution to determine the discernible quantum states and found that the high-quality epitaxy, co ...[more]

PMID: 37261718

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