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DOE OSTI · 2926608

Three-dimensional dispersion in the type-II Dirac semimetals PtTe 2 and PdTe 2 revealed through circular dichroism in angle-resolved photoemission spectroscopy

Pelayo, Ivan [California State Univ. (CalState), Long Beach, CA (United States)]·Bergner, Derek [California State Univ. (CalState), Long Beach, CA (United States)]·Williams, Archibald J. [The Ohio State Univ., Columbus, OH (United States)]·Qi, Jiayuwen [The Ohio State Univ., Columbus, OH (United States)]·Zhu, Penghao [The Ohio State Univ., Columbus, OH (United States)]·Nabi, Mahfuzun [California State Univ. (CalState), Long Beach, CA (United States)]·Huey, Warren L. B. [The Ohio State Univ., Columbus, OH (United States)]·Moreschini, Luca [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:000000018226084X)·Deng, Ziling [The Ohio State Univ., Columbus, OH (United States)] (ORCID:0000000300691828)·Hadsell, Tyler [California State Univ. (CalState), Long Beach, CA (United States)]·Denlinger, Jonathan [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)] (ORCID:0000000176451631)·Lanzara, Alessandra [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)]·Lu, Yuan-Ming [The Ohio State Univ., Columbus, OH (United States)] (ORCID:000000016275739X)·Windl, Wolfgang [The Ohio State Univ., Columbus, OH (United States)] (ORCID:0000000158920684)·Goldberger, Joshua [The Ohio State Univ., Columbus, OH (United States)] (ORCID:000000034284604X)·Ojeda-Aristizabal, Claudia [California State Univ. (CalState), Long Beach, CA (United States)] (ORCID:0000000308169727)
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Abstract

PtTe 2 and PdTe 2 are among the first transition metal dichalcogenides that were predicted to host type-II Dirac fermions, exotic particles prohibited in free space. These materials are layered and air stable, which makes them top candidates for technological applications that take advantage of their anisotropic magnetotransport properties. Here, in this work, we provide a detailed characterization of the electronic structure of PtTe 2 and PdTe 2 using angle-resolved photoemission spectroscopy (ARPES) and density functional theory calculations, offering an alternative interpretation for one of the Dirac-like dispersions in these materials. Through the use of circularly polarized light, we report a different behavior of such dispersion in PdTe 2 compared to PtTe 2 , that we relate to a symmetry analysis of the dipole matrix element. Such analysis reveals a link between the observed circular dichroism and the different momentum-dependent terms in the dispersion of these two compounds, despite their close similarity in crystal structure. Additionally, our data show a clear difference in the circular dichroic signal for the type-II Dirac cones characteristic of these materials, compared to their topologically protected surface states. Our paper provides a useful reference for the ARPES characterization of other transition metal dichalcogenides with topological properties and illustrates the use of circular dichroism as a guide to identify the topological character and attributes of two otherwise equivalent band dispersions.

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angle-resolved photoemission spectroscopydensity functional calculationsdirac semimetalelectronic structuretopological materialstopological phases of mattertransition metal dichalcogenides

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Pelayo, Ivan [California State Univ. (CalState), Long Beach, CA (United States)], Bergner, Derek [California State Univ. (CalState), Long Beach, CA (United States)], Williams, Archibald J. [The Ohio State Univ., Columbus, OH (United States)], Qi, Jiayuwen [The Ohio State Univ., Columbus, OH (United States)], Zhu, Penghao [The Ohio State Univ., Columbus, OH (United States)], Nabi, Mahfuzun [California State Univ. (CalState), Long Beach, CA (United States)], Huey, Warren L. B. [The Ohio State Univ., Columbus, OH (United States)], Moreschini, Luca [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:000000018226084X), Deng, Ziling [The Ohio State Univ., Columbus, OH (United States)] (ORCID:0000000300691828), Hadsell, Tyler [California State Univ. (CalState), Long Beach, CA (United States)], Denlinger, Jonathan [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)] (ORCID:0000000176451631), Lanzara, Alessandra [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)], Lu, Yuan-Ming [The Ohio State Univ., Columbus, OH (United States)] (ORCID:000000016275739X), Windl, Wolfgang [The Ohio State Univ., Columbus, OH (United States)] (ORCID:0000000158920684), Goldberger, Joshua [The Ohio State Univ., Columbus, OH (United States)] (ORCID:000000034284604X), Ojeda-Aristizabal, Claudia [California State Univ. (CalState), Long Beach, CA (United States)] (ORCID:0000000308169727). 2024-11-20. Three-dimensional dispersion in the type-II Dirac semimetals PtTe 2 and PdTe 2 revealed through circular dichroism in angle-resolved photoemission spectroscopy. https://doi.org/10.1103/physrevb.110.195429

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