title: Thermal conductivity of individual silicon nanoribbons.
abstract: The thermal conductivities of two groups of silicon nanoribbons of ∼20 and ∼30 nm thickness and various widths have been measured and analyzed through combining the Callaway model and the Fuchs-Sondheimer (FS) reduction function. The results show that while the data for the ∼30 nm thick ribbons can be well-explained by the classical size effect, the measured thermal conductivities for the ∼20 nm thick ribbons deviate from the prediction remarkably, and size effects beyond phonon-boundary scattering must be considered. The measurements of the Young's modulus of the thin nanoribbons yield significantly lower values than the corresponding bulk value, which could lead to a reduced phonon group velocity and subsequently thermal conductivity. This study helps to build a regime map for thermal conductivity versus nanostructures' surface-area-to-volume ratio that clearly delineates two regions where size effects beyond the Casimir limit are important or not important.
authors.affiliation: Department of Mechanical Engineering, Vanderbilt University, Nashville, TN 37235, USA. deyu.li@vanderbilt.edu.
authors.forename: Lin
authors.identifier: http://orcid.org/0000-0003-4838-5213
authors.initials: L
authors.lastname: Yang
authors.affiliation: Department of Mechanical Engineering, Vanderbilt University, Nashville, TN 37235, USA. deyu.li@vanderbilt.edu.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Mechanical Engineering, Vanderbilt University, Nashville, TN 37235, USA. deyu.li@vanderbilt.edu.
authors.forename: Qian
authors.identifier: http://orcid.org/0000-0002-2692-9729
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Mechanical Engineering, Vanderbilt University, Nashville, TN 37235, USA. deyu.li@vanderbilt.edu and School of Mechanical Engineering and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, 210096, P. R. China.
authors.forename: Yin
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Mechanical Engineering and Engineering Science, The University of North Carolina at Charlotte, Charlotte, NC 28223, USA.
authors.forename: Youfei
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Department of Mechanical Engineering and Engineering Science, The University of North Carolina at Charlotte, Charlotte, NC 28223, USA.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Guan
authors.affiliation: Department of Mechanical Engineering, Vanderbilt University, Nashville, TN 37235, USA. deyu.li@vanderbilt.edu.
authors.forename: Matthew
authors.initials: M
authors.lastname: Gerboth
authors.affiliation: School of Mechanical Engineering and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, 210096, P. R. China.
authors.forename: Juekuan
authors.initials: J
authors.lastname: Yang
authors.affiliation: School of Mechanical Engineering and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, 210096, P. R. China.
authors.forename: Yunfei
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Mechanical Engineering, Vanderbilt University, Nashville, TN 37235, USA. deyu.li@vanderbilt.edu.
authors.forename: D
authors.initials: D
authors.lastname: Greg Walker
authors.affiliation: Department of Mechanical Engineering and Engineering Science, The University of North Carolina at Charlotte, Charlotte, NC 28223, USA.
authors.forename: Terry T
authors.initials: TT
authors.lastname: Xu
authors.affiliation: Department of Mechanical Engineering, Vanderbilt University, Nashville, TN 37235, USA. deyu.li@vanderbilt.edu.
authors.forename: Deyu
authors.initials: D
authors.lastname: Li