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arXiv · 2406.14688

Absence of a bulk charge density wave signature in x-ray measurements of UTe$_2$

Caitlin S. Kengle·Dipanjan Chaudhuri·Xuefei Guo·Thomas A. Johnson·Simon Bettler·Wolfgang Simeth·Matthew J. Krogstad·Zahir Islam·Sheng Ran·Shanta R. Saha·Johnpierre Paglione·Nicholas P. Butch·Eduardo Fradkin·Vidya Madhavan·Peter Abbamonte
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Abstract

The long-sought pair density wave (PDW) is an exotic phase of matter in which charge density wave (CDW) order is intertwined with the amplitude or phase of coexisting, superconducting order \cite{Berg2009,Berg2009b}. Originally predicted to exist in copper-oxides, circumstantial evidence for PDW order now exists in a variety of materials. Recently, scanning tunneling microscopy (STM) studies have reported evidence for a three-component charge density wave (CDW) at the surface of the heavy-fermion superconductor, UTe$_2$, persisting below its superconducting transition temperature. Here, we use hard x-ray diffraction measurements on crystals of UTe$_2$ at $T = 1.9$ K and $12$ K to search for a bulk signature of this CDW. Using STM measurements as a constraint, we calculate the expected locations of CDW superlattice peaks, and sweep a large volume of reciprocal space in search of a signature. We failed to find any evidence for a CDW near any of the expected superlattice positions in many Brillouin zones. We estimate an upper bound on the CDW lattice distortion of $u_{max} \lesssim 4 \times 10^{-3} \mathrm{\AA}$. Our results suggest that the CDW observed in STM is either purely electronic, somehow lacking a signature in the structural lattice, or is restricted to the material surface.

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Caitlin S. Kengle, Dipanjan Chaudhuri, Xuefei Guo, Thomas A. Johnson, Simon Bettler, Wolfgang Simeth, Matthew J. Krogstad, Zahir Islam, Sheng Ran, Shanta R. Saha, Johnpierre Paglione, Nicholas P. Butch, Eduardo Fradkin, Vidya Madhavan, Peter Abbamonte. 2024-06-20. Absence of a bulk charge density wave signature in x-ray measurements of UTe$_2$. https://doi.org/10.1103/physrevb.110.145101

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