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arXiv · 1612.04081

GeP3: A small indirect band gap 2D crystal with high carrier mobility and strong interlayer quantum confinement

Yu Jing·Yandong Ma·Yafei Li·Thomas Heine
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Abstract

We propose a two-dimensional crystal which possesses low indirect band gaps of 0.55 eV (monolayer) and 0.43 eV (bilayer) and high carrier mobilities similar to those of phosphorene: GeP3. GeP3 has a stable three-dimensional layered bulk counterpart which is metallic and is known from experiment since 1970. It has a small cleavage energy, which suggests exfoliation of bulk material as viable means for the preparation of mono- and few-layer materials. The material shows strong interlayer quantum confinement effects, resulting in a band gap reduction from mono- to bilayer, and then to a semiconductor-metal transition between bi- and triple layer. Under biaxial strain, the indirect band gap can be turned into a direct one. Pronounced light absorption in the spectral range from ~600 to 1400 nm is predicted for monolayer and bilayer and promises applications in photovoltaics.

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Yu Jing, Yandong Ma, Yafei Li, Thomas Heine. 2017-01-31. GeP3: A small indirect band gap 2D crystal with high carrier mobility and strong interlayer quantum confinement. https://doi.org/10.1021/acs.nanolett.6b05143

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