Multifunctional two-dimensional semiconductors SnP3: universal mechanism of layer-dependent electronic phase transition. (31st October 2018)

• Record Type: Journal Article
• Authors: Gong, Peng-Lai; Zhang, Fang; Huang, Liang-Feng; Zhang, Hu; Li, Liang; Xiao, Rui-Chun; Deng, Bei; Pan, Hui; Shi, Xing-Qiang
• Is Part Of: Journal of physics. Volume 30:Number 47(2018)
• Publication Date: 2018-10-31
• Subjects: metal-to-semiconductor transition -- lone-pair electrons -- two-dimensional SnP3; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/aae61b
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: Two-dimensional (2D) semiconductors SnP3 are predicted, from first-principles calculations, to host moderate band gaps (0.72 eV for monolayer and 1.07 eV for bilayer), ultrahigh carrier mobility (̃10 4 cm 2 V −1 s −1 for bilayer), strong absorption coefficients (̃10 5 cm −1 ) and good stability. Moreover, the band gap can be modulated from an indirect character into a direct one via strain engineering. For experimental accessibility, the calculated exfoliation energies of monolayer and bilayer SnP3 are smaller than those of the common arsenic-type honeycomb structures GeP3 and InP3 . More importantly, a semiconductor-to-metal transition is discovered with the layer number N > 2. We demonstrate, in remarkable contrast to the previous understandings, that such phase transition is largely driven by the correlation between lone-pair electrons of interlayer Sn and P atoms. This mechanism is universal for analogues phase transitions in arsenic-type honeycomb structures (GeP3, InP3 and SnP3 ).