Materials Computation & Modeling

Selected Publications

1. PhysRevL

   Raman Linewidth Contributions from Four-Phonon and Electron-Phonon Interactions in Graphene

   Han, Zherui, Yang, Xiaolong, Sullivan, Sean E., Feng, Tianli, Shi, Li, Li, Wu, and Ruan, Xiulin

   Phys. Rev. Lett. Jan 2022

   HTML doi
2. Phys Rev Lett

   Ultrahigh Thermal Conductivity of θ -Phase Tantalum Nitride

   Kundu, A., Yang, X., Ma, J., Feng, T., Carrete, J., Ruan, X., Madsen, G.K.H., and Li, W.

   Physical Review Letters 2021

   Abs Bib HTML doi

   Extracting long-lasting performance from electronic devices and improving their reliability through effective heat management requires good thermal conductors. Taking both three- and four-phonon scattering as well as electron-phonon and isotope scattering into account, we predict that semimetallic θ-phase tantalum nitride (θ-TaN) has an ultrahigh thermal conductivity (κ), of 995 and 820 W m-1 K-1 at room temperature along the a and c axes, respectively. Phonons are found to be the main heat carriers, and the high κ hinges on a particular combination of factors: weak electron-phonon scattering, low isotopic mass disorder, and a large frequency gap between acoustic and optical phonon modes that, together with acoustic bunching, impedes three-phonon processes. On the other hand, four-phonon scattering is found to be significant. This study provides new insight into heat conduction in semimetallic solids and extends the search for high-κ materials into the realms of semimetals and noncubic crystal structures. © 2021 American Physical Society.

   @article{Kundu2021,
     author = {Kundu, A. and Yang, X. and Ma, J. and Feng, T. and Carrete, J. and Ruan, X. and Madsen, G.K.H. and Li, W.},
     title = {Ultrahigh Thermal Conductivity of θ -Phase Tantalum Nitride},
     journal = {Physical Review Letters},
     year = {2021},
     volume = {126},
     number = {11},
     doi = {10.1103/PhysRevLett.126.115901},
     art_number = {115901},
     note = {cited By 7},
     url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85103130434&doi=10.1103%2fPhysRevLett.126.115901&partnerID=40&md5=55f0610570b084aec901d998a0b0ad5c},
     affiliation = {Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China; College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China; Institute of Materials Chemistry, TU Wien, Vienna, A-1060, Austria; School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China; Department of Mechanical Engineering, University of Utah, Salt Lake City, UT  84112, United States; School of Mechanical Engineering, Birck Nanotechnology Center, Purdue University, West Lafayette, IN  47907-2088, United States},
     publisher = {American Physical Society},
     issn = {00319007},
     coden = {PRLTA},
     pubmed_id = {33798386},
     abbrev_source_title = {Phys Rev Lett},
     document_type = {Article},
     source = {Scopus},
     bibtex_show = {true},
     selected = {true}
   }

3. Comput Phys Commun

   ShengBTE: A solver of the Boltzmann transport equation for phonons

   Li, W., Carrete, J., Katcho, N.A., and Mingo, N.

   Computer Physics Communications 2014

   Abs Bib HTML Code Website doi

   ShengBTE is a software package for computing the lattice thermal conductivity of crystalline bulk materials and nanowires with diffusive boundary conditions. It is based on a full iterative solution to the Boltzmann transport equation. Its main inputs are sets of second- and third-order interatomic force constants, which can be calculated using third-party ab-initio packages. Dirac delta distributions arising from conservation of energy are approximated by Gaussian functions. A locally adaptive algorithm is used to determine each process-specific broadening parameter, which renders the method fully parameter free. The code is free software, written in Fortran and parallelized using MPI. A complementary Python script to help compute third-order interatomic force constants from a minimum number of ab-initio calculations, using a real-space finite-difference approach, is also publicly available for download. Here we discuss the design and implementation of both pieces of software and present results for three example systems: Si, InAs and lonsdaleite. Program summary Program title: ShengBTE Catalogue identifier: AESL-v1-0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AESL-v1-0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: GNU General Public License, version 3 No. of lines in distributed program, including test data, etc.: 292 052 No. of bytes in distributed program, including test data, etc.: 1 989 781 Distribution format: tar.gz Programming language: Fortran 90, MPI. Computer: Non-specific. Operating system: Unix/Linux. Has the code been vectorized or parallelized?: Yes, parallelized using MPI. RAM: Up to several GB Classification: 7.9. External routines: LAPACK, MPI, spglib (http://spglib.sourceforge.net/) Nature of problem: Calculation of thermal conductivity and related quantities, determination of scattering rates for allowed three-phonon processes Solution method: Iterative solution, locally adaptive Gaussian broadening Running time: Up to several hours on several tens of processors. © 2014 Elsevier B.V. All rights reserved.

   @article{Li20141747,
     author = {Li, W. and Carrete, J. and Katcho, N.A. and Mingo, N.},
     title = {ShengBTE: A solver of the Boltzmann transport equation for phonons},
     journal = {Computer Physics Communications},
     year = {2014},
     volume = {185},
     number = {6},
     pages = {1747-1758},
     doi = {10.1016/j.cpc.2014.02.015},
     note = {cited By 1082},
     url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84901233974&doi=10.1016%2fj.cpc.2014.02.015&partnerID=40&md5=5f725579e2bb88b37a44710cbc4fd099},
     affiliation = {CEA, DRT, 38054 Grenoble, France},
     publisher = {Elsevier},
     issn = {00104655},
     coden = {CPHCB},
     abbrev_source_title = {Comput Phys Commun},
     document_type = {Article},
     source = {Scopus},
     code = {https://bitbucket.org/sousaw/shengbte/},
     website = {https://www.shengbte.org/},
     bibtex_show = {true},
     selected = {true}
   }