Energy Dependence of the Circular Photogalvanic Effect in the Weyl Semimetal NbIrTe4

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