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تسجيل مستخدم جديدTwo ultra-stable novel allotropes of Tellurium few-layers
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At least four two- or quasi-one- dimensional allotropes and a mixture of them were theoretically predicted or experimentally observed for low-dimensional Te, namely the {alpha}, b{eta}, {gamma}, {delta} and chiral-{alpha}+{delta} phases. Among them the {gamma} and {alpha} phases were found the most stable phases for monolayer and thicker layers, respectively. Here, we found two novel low-dimensional phases, namely the {epsilon} and {zeta} phases. The {zeta} phase is over 29 meV/Te more stable than and the {epsilon} phase shows comparable stability with the most stable monolayer {gamma} phase. The energetic difference between the {zeta} and {alpha} phases reduces with respect to the increased layer thickness and vanishes at the four-layer (12-sublayer) thickness, while this thickness increases under change doping. Both {epsilon} and {zeta} phases are metallic chains and layers, respectively. The {zeta} phase, with very strong interlayer coupling, shows quantum well states in its layer-dependent bandstructures. These results provide significantly insight into the understanding of polytypism in Te few-layers and may boost tremendous studies on properties of various few-layer phases.
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