Observation of a Charge Density Wave Incommensuration Near the Superconducting Dome in CuxTiSe2

Anshul Kogar; Gilberto A. de la Pena; Sangjun Lee; Yizhi Fang; Stella X. -L. Sun; David B. Lioi; Goran Karapetrov; Kenneth D. Finkelstein; Jacob P. C. Ruff; Peter Abbamonte; Stephan Rosenkranz

doi:10.1103/physrevlett.118.027002

arXiv · 1608.05957

Observation of a Charge Density Wave Incommensuration Near the Superconducting Dome in CuxTiSe2

Anshul Kogar·Gilberto A. de la Pena·Sangjun Lee·Yizhi Fang·Stella X. -L. Sun·David B. Lioi·Goran Karapetrov·Kenneth D. Finkelstein·Jacob P. C. Ruff·Peter Abbamonte·Stephan Rosenkranz

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Abstract

X-ray diffraction was employed to study the evolution of the charge density wave (CDW) in CuxTiSe2 as a function of copper intercalation in order to clarify the relationship between the CDW and superconductivity. The results show a CDW incommensuration arising at an intercalation value coincident with the onset of superconductivity at around x=0.055(5). Additionally, it was found that the charge density wave persists to higher intercalant concentrations than previously assumed, demonstrating that the CDW does not terminate inside the superconducting dome. A charge density wave peak was observed in samples up to x=0.091(6), the highest copper concentration examined in this study. The phase diagram established in this work suggests that charge density wave incommensuration may play a role in the formation of the superconducting state.

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Anshul Kogar, Gilberto A. de la Pena, Sangjun Lee, Yizhi Fang, Stella X. -L. Sun, David B. Lioi, Goran Karapetrov, Kenneth D. Finkelstein, Jacob P. C. Ruff, Peter Abbamonte, Stephan Rosenkranz. 2017-01-13. Observation of a Charge Density Wave Incommensuration Near the Superconducting Dome in CuxTiSe2. https://doi.org/10.1103/physrevlett.118.027002

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