Measuring the Thermal Conductivity of Semiconductors and Semimetals Using Raman Spectroscopy

ORAL

Abstract

We present a measurement of the thermal conductivity for Bi2Se3 and Te and semimetals at room temperature by using Raman scattering spectroscopy on a clean prepared sample on a SiO2 substrate. Aluminum is deposited on either side of the flake and is used as a heat sink at room temperature. Using a He/Ne laser (633 nm), we measure the Raman shift of the sample as a function of laser power between 0.1mW and 1mW. The linear red shift of Raman modes due to heating of the sample provides a measure of the temperature of the sample around the incident laser area. We calculate the thermal conductivity of the sample by solving a simplified one dimensional heat diffusion equation, ignoring the heat conduction to the ambient air and substrate. Our results for Bi2Se3 suggest a value of 4 W/mK for the thermal conductivity, comparable to the measurements of others; using the same technique we plan make measurements of several Weyl semimetals (eg/ WTe2 and NbIrTe4).

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Presenters

  • Iraj Abbasian Shojaei

    Department of Physics, University of Cincinnati

Authors

  • Iraj Abbasian Shojaei

    Department of Physics, University of Cincinnati

  • Giriraj Jnawali

    Department of Physics, University of Cincinnati

  • Seyyedesadaf Pournia

    Department of Physics, University of Cincinnati

  • Samuel M Linser

    Department of Physics, University of Cincinnati

  • Howard E Jackson

    Department of Physics, University of Cincinnati

  • Leigh Smith

    Department of Physics, University of Cincinnati, Physics, University of Cincinnati

  • Ryan Need

    National Institute of Standards and Technology, Materials Department, University of California, Santa Barbara, NIST Center for Neutron Research, National Institute for Standards and Technology

  • Stephen Wilson

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