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A New Silicon Phase with Direct Band Gap and Novel Optoelectronic Properties.

ABSTRACT: Due to the compatibility with the well-developed Si-based semiconductor industry, there is considerable interest in developing silicon structures with direct energy band gaps for effective sunlight harvesting. In this paper, using silicon triangles as the building block, we propose a new silicon allotrope with a direct band gap of 0.61?eV, which is dynamically, thermally and mechanically stable. Symmetry group analysis further suggests that dipole transition at the direct band gap is allowed. In addition, this new allotrope displays large carrier mobility (~10(4)?cm/V?·?s) at room temperature and a low mass density (1.71?g/cm(3)), making it a promising material for optoelectronic applications.

SUBMITTER: Guo Y

PROVIDER: S-EPMC4585815 | biostudies-other | 2015

REPOSITORIES: biostudies-other

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A New Silicon Phase with Direct Band Gap and Novel Optoelectronic Properties.

Guo Yaguang Y Wang Qian Q Kawazoe Yoshiyuki Y Jena Puru P

Scientific reports 20150923

Due to the compatibility with the well-developed Si-based semiconductor industry, there is considerable interest in developing silicon structures with direct energy band gaps for effective sunlight harvesting. In this paper, using silicon triangles as the building block, we propose a new silicon allotrope with a direct band gap of 0.61 eV, which is dynamically, thermally and mechanically stable. Symmetry group analysis further suggests that dipole transition at the direct band gap is allowed. In ...[more]

PMID: 26395926

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