2021年第82回応用物理学会秋季学術講演会

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22 合同セッションM 「フォノンエンジニアリング」 » 22.1 合同セッションM 「フォノンエンジニアリング」

[13a-N106-1~5] 22.1 合同セッションM 「フォノンエンジニアリング」

2021年9月13日(月) 10:30 〜 11:45 N106 (口頭)

渡邉 孝信(早大)

11:00 〜 11:15

[13a-N106-3] Unconventional, Controllable Tuning of Thermal Conductance Across Vertically Layered van der Waals Materials via Ionic Intercalation

〇(P)Wenyu Yuan1、Kan Ueji1、Takashi Yagi2、Hong En Lim1、Takahiko Endo1、Yasumitsu Miyata1、Yohei Yomogida1、Kazuhiro Yanagi1 (1.Tokyo Metropolitan Univ.、2.AIST)

キーワード:thermal conductance, intercalation, van der Waals

The controllable tuning of thermal conduction of solids is of critical significance for the development of advanced electronics and the efficiency for thermal energy conversion. The electrochemical intercalation strategy is highly desirable due to the wide applicability and practicality.[1] Conventional thermophysical knowledge suggests that the insertion of heteroatoms into lattices trends suppress thermal transport due to the enhanced phonon scattering effect and symmetry breaking.[2-3] Here, we reported an unconventional correlation between G and insertion of cations into the stacked vdW materials. All stacked materials are obtained via a layer-by-layer transfer method using monolayer MoS2 film. The intercalation of K+ is achieved via an electrochemical gating method (Figure 1a), in which the K+ concentration is controllably tuned via gate voltage (Vg). The TDTR phase degree obviously changes with the applied Vg (Figure 1b, 1c). The plots of calculated G values versus Vg (Figure 1d) demonstrate that G nearly linearly increases with the concentration of K+, and reversibly decreases with the deintercalation of K+ with an on/off ratio in G of ~200%. The unconventional interaction-dependent G is may originated from that inserted heteroatoms promote the transport of high-frequency phonons at vdW gap.
References: [1] Lu, Q., Huberman, S., Zhang, H. et al. Nat. Mater. 19, 655–662 (2020). [2] Zhu, G., Liu, J., Zheng, Q. et al. Nat. Commun. 7, 13211 (2016). [3] Kang, J. S., Ke, M., Hu, Y. Nano Lett. 17, 1431-1438. (2017).