Quasi-Two-Dimensional Heterostructures (KM_1 – xTe)(LaTe₃) (M = Mn and Zn) with Charge Density Waves

Journal Article · Mon Mar 08 00:00:00 EST 2021 · Chemistry of Materials

DOI:https://doi.org/10.1021/acs.chemmater.0c04923· OSTI ID:1779060

Bao, Jin-Ke  ^[1]; Malliakas, Christos D.  ^[2]; Zhang, Chi ^[2]; Cai, Songting  ^[2]; Chen, Haijie ^[3]; Rettie, Alexander E.  ^[4]; Fisher, Brandon L. ^[5]; Chung, Duck Young ^[6]; Dravid, Vinayak P.  ^[2]; Kanatzidis, Mercouri G.  ^[3]

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1. Argonne National Lab. (ANL), Lemont, IL (United States); Univ. of Bayreuth (Germany)
2. Northwestern Univ., Evanston, IL (United States)
3. Argonne National Lab. (ANL), Lemont, IL (United States); Northwestern Univ., Evanston, IL (United States)
4. Univ. College London (United Kingdom)
5. Argonne National Lab. (ANL), Lemont, IL (United States). Center for Nanoscale Materials
6. Argonne National Lab. (ANL), Lemont, IL (United States)

Layered heterostructure materials with two different functional building blocks can teach us about emergent physical properties and phenomena arising from interactions between the layers. Here, we report intergrowth compounds KLaM_{1 - x}Te₄ (M = Mn and Zn; $$x \approx$$ 0.35) featuring two chemically distinct alternating layers [LaTe₃] and [KM_{1 - x}Te]. Their crystal structures are incommensurate, determined by single X-ray diffraction for the Mn compound and a transmission electron microscope study for the Zn compound. KLaMn_{1 – x}Te₄ crystallizes in the orthorhombic superspace group Pmnm(01/2 gamma)s00 with lattice parameters a = 4.4815(3) Å, b = 21.6649(16) Å, and c = 4.5220(3) Å. It exhibits charge density wave order at room temperature with a modulation wave vector q = 1/2b* + 0.3478c* originating from electronic instability of Te-square nets in [LaTe₃] layers. The Mn analog exhibits a cluster spin glass behavior with spin freezing temperature $$T_f \approx$$ 5 K attributed to disordered Mn vacancies and competing magnetic interactions in the [Mn_{1 - x}Te] layers. The Zn analog also has charge density wave order at room temperature with a similar q-vector having the c* component similar to 0.346 confirmed by selected-area electron diffraction. Electron transfer from [KM_{1 - x}Te] to [LaTe₃] layers exists in KLaM_{1 – x}Te₄, leading to an enhanced electronic specific heat coefficient. The resistivities of KLaM_{1 - x}Te₄ (M = Mn and Zn) exhibit metallic behavior at high temperatures and an upturn at low temperatures, suggesting partial localization of carriers in the [LaTe₃] layers with some degree of disorder associated with the M atom vacancies in the [M_{1 - x}Te] layers.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States). Center for Nanoscale Materials
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES). Materials Sciences & Engineering Division; National Science Foundation (NSF); International Institute for Nanotechnology (IIN); Keck Foundation; State of Illinois; Alexander von Humboldt Foundation
• Grant/Contract Number: AC02-06CH11357
• OSTI ID: 1779060
• Journal Information: Chemistry of Materials, Vol. 33, Issue 6; ISSN 0897-4756
• Publisher: American Chemical Society (ACS)
• Country of Publication: United States
• Language: English