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arXiv · 2401.17437

Ultrafast measurements under anisotropic strain reveal near equivalence of competing charge orders in TbTe$_3$

Soyeun Kim·Gal Orenstein·Anisha G. Singh·Ian R. Fisher·David A. Reis·Mariano Trigo
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Abstract

We report ultrafast reflectivity measurements of the dynamics of the order parameter of the charge density wave (CDW) in TbTe$_3$ under anisotropic strain. We observe an increase in the frequency of the amplitude mode with increasing tensile strain along the $a$-axis (which drives the lattice into $a>c$, with $a$ and $c$ the lattice constants), and similar behavior for tensile strain along $c$ ($c>a$). This suggests that both strains stabilize the corresponding CDW order and further support the near equivalence of the CDW phases oriented in $a$- and $c$-axis, in spite of the orthorhombic space group. The results were analyzed within the time-dependent Ginzburg-Landau framework, which agrees well with the reflectivity dynamics.

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Soyeun Kim, Gal Orenstein, Anisha G. Singh, Ian R. Fisher, David A. Reis, Mariano Trigo. 2024-01-30. Ultrafast measurements under anisotropic strain reveal near equivalence of competing charge orders in TbTe$_3$. https://doi.org/10.1088/1361-6633/ad71ee

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