Ab initio lattice thermal conductivity of bulk and thin-film α-Al2O3. (22nd August 2018)

• Record Type: Journal Article
• Authors: Dongre, Bonny; Carrete, Jesús; Mingo, Natalio; Madsen, Georg K.H.
• Is Part Of: MRS communications. Volume 8:Number 3(2018)
• Page Start: 1119
• Page End: 1123
• Publication Date: 2018-08-22
• Subjects: Materials -- Periodicals; 620.11
• DOI: 10.1557/mrc.2018.161
• Languages: English
• ISSNs: 2159-6859

Abstract

Abstract: Abstract : The thermal conductivities ( κ ) of bulk and thin-film α -Al2 O3 are calculated from first principles using both the local density approximation (LDA) and the generalized gradient approximation (GGA) to exchange and correlation. The room temperature single-crystal LDA value ~39 W/m K agrees well with the experimental values ~35–39 W/m K, whereas the GGA values are much smaller ~26 W/m K. Throughout the temperature range, LDA is found to slightly overestimate κ, whereas GGA strongly underestimates it. We calculate the κ of crystalline α -Al2 O3 thin films and observe a maximum of 79% reduction for 10 nm thickness.