title: Conductivity-limiting bipolar thermal conductivity in semiconductors.
abstract: Intriguing experimental results raised the question about the fundamental mechanisms governing the electron-hole coupling induced bipolar thermal conduction in semiconductors. Our combined theoretical analysis and experimental measurements show that in semiconductors bipolar thermal transport is in general a "conductivity-limiting" phenomenon, and it is thus controlled by the carrier mobility ratio and by the minority carrier partial electrical conductivity for the intrinsic and extrinsic cases, respectively. Our numerical method quantifies the role of electronic band structure and carrier scattering mechanisms. We have successfully demonstrated bipolar thermal conductivity reduction in doped semiconductors via electronic band structure modulation and/or preferential minority carrier scatterings. We expect this study to be beneficial to the current interests in optimizing thermoelectric properties of narrow gap semiconductors.
authors.affiliation: Materials Science and Engineering Department, University of Washington, Seattle, WA 98195-2120, USA.
authors.forename: Shanyu
authors.initials: S
authors.lastname: Wang
authors.affiliation: Materials Science and Engineering Department, University of Washington, Seattle, WA 98195-2120, USA.
authors.forename: Jiong
authors.initials: J
authors.lastname: Yang
authors.affiliation: Materials Science and Engineering Department, University of Washington, Seattle, WA 98195-2120, USA.
authors.forename: Trevor
authors.initials: T
authors.lastname: Toll
authors.affiliation: Materials Science and Engineering Department, University of Washington, Seattle, WA 98195-2120, USA.
authors.forename: Jihui
authors.initials: J
authors.lastname: Yang
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China.
authors.forename: Wenqing
authors.initials: W
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China.
authors.forename: Xinfeng
authors.initials: X
authors.lastname: Tang