Moving the heat aside with BAs Thermal management becomes increasingly important as we decrease device size and increase computing power. Engineering materials with high thermal conductivity, such as boron arsenide (BAs), is hard because it is essential to avoid defects and impurities during synthesis, which would stop heat flow. Three different research groups have synthesized BAs with a thermal conductivity around 1000 watts per meter-kelvin: Kang et al., Li et al., and Tian et al. succeeded in synthesizing high-purity BAs with conductivities half that of diamond but more than double that of conventional metals (see the Perspective by Dames). The advance validates the search for high-thermal-conductivity materials and provides a new material that may be more easily integrated into semiconducting devices. Science, this issue p. 575, p. 579, p. 582; see also p. 549 Boron arsenide has an ultrahigh thermal conductivity, making it competitive with diamond for thermal management applications. Improving the thermal management of small-scale devices requires developing materials with high thermal conductivities. The semiconductor boron arsenide (BAs) is an attractive target because of ab initio calculation indicating that single crystals have an ultrahigh thermal conductivity. We synthesized BAs single crystals without detectable defects and measured a room-temperature thermal conductivity of 1300 watts per meter-kelvin. Our spectroscopy study, in conjunction with atomistic theory, reveals that the distinctive band structure of BAs allows for very long phonon mean free paths and strong high-order anharmonicity through the four-phonon process. The single-crystal BAs has better thermal conductivity than other metals and semiconductors. Our study establishes BAs as a benchmark material for thermal management applications and exemplifies the power of combining experiments and ab initio theory in new materials discovery.

中文翻译：

---

砷化硼高热导率的实验观察

随着我们减小设备尺寸并提高计算能力，热管理变得越来越重要。砷化硼 (BA) 等具有高导热性的工程材料很硬，因为在合成过程中必须避免缺陷和杂质，这会阻止热流。三个不同的研究小组合成了热导率约为 1000 瓦/米-开尔文的 BA：Kang 等人、Li 等人和 Tian 等人。成功合成了高纯度 BA，其导电性是金刚石的一半，但是传统金属的两倍以上（参见 Dames 的观点）。这一进展证实了对高导热材料的探索，并提供了一种可以更容易地集成到半导体器件中的新材料。科学，这个问题 p。575 页。579 页。582; 另见第。549 砷化硼具有超高的导热性，使其在热管理应用中可与金刚石相媲美。改善小型设备的热管理需要开发具有高导热性的材料。半导体砷化硼 (BAs) 是一个有吸引力的目标，因为 ab initio 计算表明单晶具有超高的热导率。我们合成了没有可检测缺陷的 BAs 单晶，并测量了每米开尔文 1300 瓦的室温热导率。我们的光谱研究与原子理论相结合，揭示了 BA 的独特能带结构允许通过四声子过程获得非常长的声子平均自由程和强高阶非谐性。单晶BAs比其他金属和半导体具有更好的导热性。我们的研究将 BA 确立为热管理应用的基准材料，并举例说明了在新材料发现中将实验和从头算理论相结合的力量。