2025-10-02 東京大学,科学技術振興機構
熱振動抑制により100 cm2V-1s-1を超える移動度を達成
＜関連情報＞
- https://www.k.u-tokyo.ac.jp/information/category/press/0027759.html
- https://www.k.u-tokyo.ac.jp/assets/WEB_有機半導体で従来比10倍となる100cm2V-1s-1超の移動度を達成.pdf
- https://www.science.org/doi/10.1126/sciadv.aea1634
歪んだ有機半導体で100 cm2 V −1s−1を超えるホール移動度を観測 Hall mobility exceeding 100 cm2 V−1 s−1 observed in strained organic semiconductors
Tomoki Furukawa, Naotaka Kasuya, Hideaki Takayanagi, Shun Watanabe, and Jun Takeya
Science Advances Published:1 Oct 2025
DOI:https://doi.org/10.1126/sciadv.aea1634
Abstract
A highly periodic electrostatic potential and coherent band transport can emerge in organic molecular crystals, despite weak van der Waals interactions. Although charge carrier mobility in single-crystalline organic semiconductors (OSCs) reaches 10 square centimeters per volt per second (cm2 V−1 s−1), it is predominantly limited by molecular vibrations excited at room temperature. The extent to which mobility in single-crystalline OSCs can be increased remains a central question. Here, we demonstrate charge transport in a clean two-dimensional hole gas (2DHG) in uniaxially strained, single-crystalline OSCs at cryogenic temperatures, with minimized lattice vibrations. Hall effect measurements reveal a mobility of 117 cm2 V−1 s−1 at 2 kelvin under 2.8% compressional strain, with an extraordinarily large piezoresistive effect and low sheet resistivity of 550 ohms, one-fifth of the lowest resistivity in unstrained samples. These clean systems offer opportunities to explore intrinsic strain-induced charge transport physics, where condensed matter phenomena, characterized by weakly bonded molecular orbitals, combine electronic correlation and lattice degrees of freedom.
