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Discovery of colossal Seebeck effect in metallic Cu2Se.

ABSTRACT: Both electrical conductivity ? and Seebeck coefficient S are functions of carrier concentration being correlated with each other, and the value of power factor S2? is generally limited to less than 0.01?W?m-1?K-2. Here we report that, under the temperature gradient applied simultaneously to both parallel and perpendicular directions of measurement, a metallic copper selenide, Cu2Se, shows two sign reversals and colossal values of S exceeding ±2?mV?K-1 in a narrow temperature range, 340?K?

SUBMITTER: Byeon D

PROVIDER: S-EPMC6325113 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Discovery of colossal Seebeck effect in metallic Cu2Se.

Byeon Dogyun D Sobota Robert R Delime-Codrin Kévin K Choi Seongho S Hirata Keisuke K Adachi Masahiro M Kiyama Makoto M Matsuura Takashi T Yamamoto Yoshiyuki Y Matsunami Masaharu M Takeuchi Tsunehiro T

Nature communications 20190108 1

Both electrical conductivity σ and Seebeck coefficient S are functions of carrier concentration being correlated with each other, and the value of power factor S2σ is generally limited to less than 0.01 W m-1 K-2. Here we report that, under the temperature gradient applied simultaneously to both parallel and perpendicular directions of measurement, a metallic copper selenide, Cu2Se, shows two sign reversals and colossal values of S exceeding ±2 mV K<su ...[more]

PMID: 30622265

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