Enhanced Electron Heat Conduction in TaS3 1D Metal Wire

• Published in: Materials Vol. 14; no. 16; p. 4477
• Main Authors: Yi, Hojoon, Bahng, Jaeuk, Park, Sehwan, Dang, Dang Xuan, Sakong, Wonkil, Kang, Seungsu, Ahn, Byung-wook, Kim, Jungwon, Kim, Ki Kang, Lim, Jong Tae, Lim, Seong Chu
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 10.08.2021; MDPI
• Subjects: charge density wave; Conduction heating; Conductive heat transfer; Electric currents; Electrical resistivity; Electrodes; heat conduction; Heat conductivity; Lorenz number; Metals; Nanowires; Peierls transition; Room temperature; Thermal conductivity; Thermodynamic properties; Transition temperature; Wiedemann–Franz law; Wire; X-rays; United States > US
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma14164477

The 1D wire TaS3 exhibits metallic behavior at room temperature but changes into a semiconductor below the Peierls transition temperature (Tp), near 210 K. Using the 3ω method, we measured the thermal conductivity κ of TaS3 as a function of temperature. Electrons dominate the heat conduction of a metal. The Wiedemann–Franz law states that the thermal conductivity κ of a metal is proportional to the electrical conductivity σ with a proportional coefficient of L0, known as the Lorenz number—that is, κ=σLoT. Our characterization of the thermal conductivity of metallic TaS3 reveals that, at a given temperature T, the thermal conductivity κ is much higher than the value estimated in the Wiedemann–Franz (W-F) law. The thermal conductivity of metallic TaS3 was approximately 12 times larger than predicted by W-F law, implying L=12L0. This result implies the possibility of an existing heat conduction path that the Sommerfeld theory cannot account for.