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DOE OSTI · 2861659

Realignment and suppression of charge density waves in the rare-earth tritellurides 𝑅⁢Te 3 (𝑅 = La, Gd, Er)

Siddique, Saif [Cornell University, Ithaca, NY (United States)] (ORCID:0000000303001087)·Hart, James L. [Cornell University, Ithaca, NY (United States)] (ORCID:0000000229606925)·Niedzielski, Drake [Cornell University, Ithaca, NY (United States)] (ORCID:0000000296078042)·Singha, Ratnadwip [Princeton University, NJ (United States); Indian Institute of Technology Guwahati, Assam (India)] (ORCID:0000000231552137)·Han, Myung-Geun [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000237363281)·Funni, Stephen D. [Cornell University, Ithaca, NY (United States)]·Colletta, Michael [Cornell University, Ithaca, NY (United States)] (ORCID:0000000225718954)·Kiani, Mehrdad T. [Cornell University, Ithaca, NY (United States)] (ORCID:000000029301457X)·Schnitzer, Noah [Cornell University, Ithaca, NY (United States)] (ORCID:0000000210421146)·Williams, Natalie L. [Cornell University, Ithaca, NY (United States)]·Kourkoutis, Lena F. [Cornell University, Ithaca, NY (United States)]·Zhu, Yimei [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000216387217)·Schoop, Leslie M. [Princeton University, NJ (United States)] (ORCID:0000000334594241)·Arias, Tomás A. [Cornell University, Ithaca, NY (United States)] (ORCID:0000000158800260)·Cha, Judy J. [Cornell University, Ithaca, NY (United States)] (ORCID:0000000263462814)
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Abstract

The rare-earth tritellurides have a rich phase diagram that includes charge density waves (CDWs), superconductivity, and magnetic order, offering a platform to study the interplay between these phases on a square-net system. Prior studies have shown that defects can affect the CDW characteristics in these materials, yet coupling between the CDW order and the underlying microstructure has not been studied at the nanoscale. Here we use scanning transmission electron microscopy at cryogenic temperatures to directly visualize the effects of defects on the CDW order and provide a spatially resolved microscopic correlation between the CDW transition and structural defects. Here, we show that in the presence of extended defects, such as dislocations and stacking faults, the weak orthorhombicity of the rare-earth tritellurides is lost and the material becomes pseudotetragonal. Since the orthorhombicity acts as a symmetry breaking field for the CDW transitions in rare-earth tritellurides, the presence of these extended defects modulates the energetics of the CDWs and suppresses the ground-state CDW phase at low temperature.

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Charge density wavesCryo-transmission electron microscopyCrystal defectsDisclinations & dislocationsElectron diffractionRare-earth magnetic materialsScanning transmission electron microscopyTransmission electron microscopy

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Siddique, Saif [Cornell University, Ithaca, NY (United States)] (ORCID:0000000303001087), Hart, James L. [Cornell University, Ithaca, NY (United States)] (ORCID:0000000229606925), Niedzielski, Drake [Cornell University, Ithaca, NY (United States)] (ORCID:0000000296078042), Singha, Ratnadwip [Princeton University, NJ (United States); Indian Institute of Technology Guwahati, Assam (India)] (ORCID:0000000231552137), Han, Myung-Geun [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000237363281), Funni, Stephen D. [Cornell University, Ithaca, NY (United States)], Colletta, Michael [Cornell University, Ithaca, NY (United States)] (ORCID:0000000225718954), Kiani, Mehrdad T. [Cornell University, Ithaca, NY (United States)] (ORCID:000000029301457X), Schnitzer, Noah [Cornell University, Ithaca, NY (United States)] (ORCID:0000000210421146), Williams, Natalie L. [Cornell University, Ithaca, NY (United States)], Kourkoutis, Lena F. [Cornell University, Ithaca, NY (United States)], Zhu, Yimei [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000216387217), Schoop, Leslie M. [Princeton University, NJ (United States)] (ORCID:0000000334594241), Arias, Tomás A. [Cornell University, Ithaca, NY (United States)] (ORCID:0000000158800260), Cha, Judy J. [Cornell University, Ithaca, NY (United States)] (ORCID:0000000263462814). 2024-07-25. Realignment and suppression of charge density waves in the rare-earth tritellurides 𝑅⁢Te 3 (𝑅 = La, Gd, Er). https://doi.org/10.1103/physrevb.110.014111

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