Energy Dependence of the Circular Photogalvanic Effect in the Weyl Semimetal NbIrTe<sub>4</sub>

ORAL

Abstract

We have investigated the Circular Photogalvanic Effect (CPGE) in the orthorhombic ternary compound, NbIrTe4. This material has been suggested theoretically as a type-II Weyl semimetal having 8 pairs of Weyl nodes, but no ARPES measurements have been published as yet. Measuring the photoresponse of a device fabricated from a thin film of this material (~100 nm thickness) under (0.3-1) eV illumination using a quarter-wave plate, reveals a clear energy dependent CPGE, increasing by as the photon energy approaches the Fermi energy. On top of this broad increase, there exists an energy resonance for the CPGE signal at ~0.6 eV. An underlying linear polarization-dependent photoresponse of the device from the photothermoelectric effect (PTE) is seen to decrease by an order of magnitude at lower energies. This PTE response has been measured in a broad energy range (0.3-1.8eV) using a linearly polarized light along two main crystal axes, and is in good agreement with DFT calculations.

*We acknowledge the financial support of the NSF through grants DMR 1507844, DMR 1531373, and ECCS 1509706. S.D.W. acknowledges the support of UCSB Quantum Foundry, NSF DMR-1906325 and NSF DMR-1720256. CL and FZ acknowledge NSF of China through grant 11674278.

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Presenters

  • Seyyedesadaf Pournia

    • University Of Cincinnati

Authors

  • Seyyedesadaf Pournia

    • University Of Cincinnati

  • Giriraj Jnawali

    • University Of Cincinnati

  • Samuel M Linser

    • University Of Cincinnati

  • Iraj Abbasian Shojaei

    • University Of Cincinnati

  • Howard E Jackson

    • University Of Cincinnati

  • Leigh Smith

    • University Of Cincinnati

  • Congcong Le

    • Max Planck Institute for Chemical Physics of Solids

  • Fu-Chun Zhang

    • Kavli Institute of Theoretical Sciences, University of the Chinese Academy of Sciences
    • Kavli Institute of Theoretical Sciences, University of the Chinese Academy of Science

  • Brenden Ortiz

    • University of California, Santa Barbara
    • Materials Department, UC Santa Barbara

  • Stephen D. Wilson

    • Materials Department, UC Santa Barbara
    • Materials Department, University of California, Santa Barbara, California 93106-5050, USA
    • Materials, University of Santa Barbara
    • Materials Department, University of California, Santa Barbara