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Miao, H

Publications and source records attributed to Miao, H.

6 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Structure of Charge Density Waves in La1.875Ba0.125CuO4

Although charge-density wave (CDW) correlations exist in several families of cuprate superconductors, they exhibit substantial variation in CDW wavevector and correlation length, indicating a key role for CDW-lattice interactions. We investigated this interaction in La1.875Ba0.125CuO4 using single crystal x-ray diffraction to collect a large number of CDW peak intensities, and determined the Cu and La/Ba atomic distortions induced by the formation of CDW order. Within the CuO2 planes, the distortions involve a periodic modulation of the Cu-Cu spacing along the direction of the ordering wave vector. The charge ordering within the copper-oxygen layer induces an out-of-plane breathing modulation of the surrounding lanthanum layers, which leads to a related distortion on the adjacent copper-oxygen layer. Our result implies that the CDW-related structural distortions do not remain confined to a single layer but rather propagate an appreciable distance through the crystal. This leads to overlapping structural modulations, in which CuO2 planes exhibit distortions arising from the orthogonal CDWs in adjacent layers as well as distortions from the CDW within the layer itself. We attribute this striking effect to the weak c-axis charge screening in cuprates and suggest this effect could help couple the CDW between adjacent planes in the crystal.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2012

Isotropic Superconducting Gaps with Enhanced Pairing on Electron Fermi Surfaces in FeTe0.55Se0.45

We used angle-resolved photoemission spectroscopy to reveal directly the momentum distribution of the superconducting gap in FeTe{sub 1-x}Se{sub x}, which has the simplest structure of all Fe-based superconductors. We found isotropic superconducting gaps on all Fermi surfaces whose sizes can be fitted by a single gap function derived from a strong coupling approach, promoting local antiferromagnetic exchange interactions as a serious candidate for the pairing origin.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗