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Title: Reduction of thermal conductivity in MnSi{sub 1.7} multi-layered thin films with artificially inserted Si interfaces

Abstract

We report a lowered lattice thermal conductivity in nm-scale MnSi{sub 1.7}/Si multilayers which were fabricated by controlling thermal diffusions of Mn and Si atoms. The thickness of the constituent layers is 1.5–5.0 nm, which is comparable to the phonon mean free path of both MnSi{sub 1.7} and Si. By applying the above nanostructures, we reduced the lattice thermal conductivity down to half that of bulk MnSi{sub 1.7}/Si composite materials. The obtained value of 1.0 W/K m is the experimentally observed minimum in MnSi{sub 1.7}-based materials without any heavy element doping and close to the minimum thermal conductivity. We attribute the reduced lattice thermal conductivity to phonon scattering at the MnSi{sub 1.7}/Si interfaces in the multilayers.

Authors:
; ; ; ;  [1]
  1. Center for Exploratory Research, Research & Development Group, Hitachi Ltd., 1-280, Higashi-koigakubo, Kokubunji, Tokyo 185-8601 (Japan)
Publication Date:
OSTI Identifier:
22594358
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; COMPARATIVE EVALUATIONS; COMPOSITE MATERIALS; INTERFACES; LAYERS; MANGANESE SILICIDES; MEAN FREE PATH; NANOSTRUCTURES; PHONONS; REDUCTION; SCATTERING; SILICON; THERMAL CONDUCTIVITY; THERMAL DIFFUSION; THICKNESS; THIN FILMS

Citation Formats

Kurosaki, Y., E-mail: yosuke.kurosaki.uy@hitachi.com, Yabuuchi, S., Nishide, A., Fukatani, N., and Hayakawa, J.. Reduction of thermal conductivity in MnSi{sub 1.7} multi-layered thin films with artificially inserted Si interfaces. United States: N. p., 2016. Web. doi:10.1063/1.4960634.
Kurosaki, Y., E-mail: yosuke.kurosaki.uy@hitachi.com, Yabuuchi, S., Nishide, A., Fukatani, N., & Hayakawa, J.. Reduction of thermal conductivity in MnSi{sub 1.7} multi-layered thin films with artificially inserted Si interfaces. United States. doi:10.1063/1.4960634.
Kurosaki, Y., E-mail: yosuke.kurosaki.uy@hitachi.com, Yabuuchi, S., Nishide, A., Fukatani, N., and Hayakawa, J.. Mon . "Reduction of thermal conductivity in MnSi{sub 1.7} multi-layered thin films with artificially inserted Si interfaces". United States. doi:10.1063/1.4960634.
@article{osti_22594358,
title = {Reduction of thermal conductivity in MnSi{sub 1.7} multi-layered thin films with artificially inserted Si interfaces},
author = {Kurosaki, Y., E-mail: yosuke.kurosaki.uy@hitachi.com and Yabuuchi, S. and Nishide, A. and Fukatani, N. and Hayakawa, J.},
abstractNote = {We report a lowered lattice thermal conductivity in nm-scale MnSi{sub 1.7}/Si multilayers which were fabricated by controlling thermal diffusions of Mn and Si atoms. The thickness of the constituent layers is 1.5–5.0 nm, which is comparable to the phonon mean free path of both MnSi{sub 1.7} and Si. By applying the above nanostructures, we reduced the lattice thermal conductivity down to half that of bulk MnSi{sub 1.7}/Si composite materials. The obtained value of 1.0 W/K m is the experimentally observed minimum in MnSi{sub 1.7}-based materials without any heavy element doping and close to the minimum thermal conductivity. We attribute the reduced lattice thermal conductivity to phonon scattering at the MnSi{sub 1.7}/Si interfaces in the multilayers.},
doi = {10.1063/1.4960634},
journal = {Applied Physics Letters},
number = 6,
volume = 109,
place = {United States},
year = {Mon Aug 08 00:00:00 EDT 2016},
month = {Mon Aug 08 00:00:00 EDT 2016}
}
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