Suppression of stacking order with doping in 1T-TaS$_{2-x}$Se$_x$

Sharon S. Philip; Despina Louca; J. C. Neuefeind; Matthew B. Stone; A. I. Kolesnikov

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arXiv · 2309.13460

Suppression of stacking order with doping in 1T-TaS$_{2-x}$Se$_x$

Sharon S. Philip·Despina Louca·J. C. Neuefeind·Matthew B. Stone·A. I. Kolesnikov

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Abstract

In 1T-TaS$_{2-x}$Se$_x$, the charge density wave (CDW) state features a star of David lattice that expands across layers as the system becomes commensurate on cooling. The layers can also order along the c-axis and different stacking orders have been proposed. Using neutron scattering on powder samples, we compared the stacking order previously observed in 1T-TaS$_2$ as the system is doped with Se. While at low temperature, a 13c layer sequence stacking was observed in TaS$_2$, this type of ordering was not evident with doping. Doping with Se results in a nearly commensurate state with the Mott state suppressed which may be linked to the absence of the layer stacking.

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Sharon S. Philip, Despina Louca, J. C. Neuefeind, Matthew B. Stone, A. I. Kolesnikov. 2023-09-23. Suppression of stacking order with doping in 1T-TaS$_{2-x}$Se$_x$. https://arxiv.org/abs/2309.13460

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