Experimental evidence of a stable 2&lt;em&gt;H&lt;/em&gt; phase on the surface of layered 1&lt;em&gt;T&lt;/em&gt;′-TaTe&lt;sub&gt;2&lt;/sub&gt;

Kar, Indrani; Dolui, Kapildeb; Harnagea, Luminita; Kushnirenko, Yevhen; Shipunov, Grigory; Plumb, Nicholas C.; Shi, Ming; Büchner, Bernd; Thirupathaiah, Setti

doi:10.1021/acs.jpcc.0c10517

Experimental evidence of a stable 2H phase on the surface of layered 1T′-TaTe₂

Kar I, Dolui K, Harnagea L, Kushnirenko Y, Shipunov G, Plumb NC, Shi M, Büchner B & Thirupathaiah S

Citation

Kar, I., Dolui, K., Harnagea, L., Kushnirenko, Y., Shipunov, G., Plumb, N. C., … Thirupathaiah, S. (2021). Experimental evidence of a stable 2H phase on the surface of layered 1T′-TaTe₂. Journal of Physical Chemistry C, 125(1), 1150-1156. https://doi.org/10.1021/acs.jpcc.0c10517

Persistent URL https://www.dora.lib4ri.ch/psi/islandora/object/psi:36775

We report on the low-energy electronic structure of tantalum ditelluride (1T′-TaTe₂), one of the charge density wave (CDW) materials from the group V transition metal dichalcogenides using angle-resolved photoemission spectroscopy and density functional theory (DFT). We find that the Fermi surface topology of TaTe₂ is quite complicated compared to its isovalent compounds such as TaS₂, TaSe₂, and isostructural compound NbTe₂. Most importantly, we discover that the surface electronic structure of 1T′-TaTe₂ has more resemblance to the 2H-TaTe₂, while the bulk electronic structure has more resemblance to the hypothetical 1T-TaTe₂. These experimental observations are thoroughly compared with our DFT calculations performed on 1T-, 2H-, and 2H (monolayer)/1T-TaTe₂. We further notice that the Fermi surface topology is temperature independent up to 180 K, confirming that the 2H phase on the surface is stable up to 180 K and the CDW order is not due to the Fermi surface nesting.