Abstract We investigate the carrier transport mechanism in Br-doped SnSe2 single crystals by characterizing electrical properties in the high-temperature (T) region (300–500 K). In-plane electrical resistivity decreases with the introduction of Br dopant in layered SnSe2 single crystals owing to the increase of the electron carrier concentration (ne), indicating Br is an efficient electron donor for SnSe2. From the T dependence of ne, the thermally activated behavior disappears when ne exceeds approximately 1018 cm−3, suggesting degenerate conduction easily occurs by electron doping from 300 to 500 K. The Hall carrier mobility (μH) depends on T according to the relation μH ~ T−γ, and γ is significantly reduced from 1.68 to 0.52 by Br doping. This strongly evidences that the homopolar optical mode phonon, as the main scatterer for carrier transport at high T, is effectively quenched through the carrier doping.

中文翻译：

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Br掺杂SnSe2单晶载流子传输机制研究

摘要 我们通过表征高温 (T) 区 (300–500 K) 的电学性质来研究 Br 掺杂的 SnSe2 单晶中的载流子传输机制。由于电子载流子浓度 (ne) 的增加，随着在层状 SnSe2 单晶中引入 Br 掺杂剂，面内电阻率降低，表明 Br 是 SnSe2 的有效电子供体。从 ne 的 T 依赖性来看，当 ne 超过大约 1018 cm-3 时热激活行为消失，表明电子掺杂从 300 到 500 K 容易发生简并传导。 根据关系 μH，霍尔载流子迁移率 (μH) 取决于 T ~ T−γ，并且通过 Br 掺杂，γ 从 1.68 显着降低到 0.52。这有力地证明了单极光学模式声子，