Six new silicon phases with direct band gaps

Abstract

Six new silicon phases with direct band gaps were found through silicon atomic substitution of carbon in the known carbon structures via high-throughput calculations.

High-throughput calculation screening for new silicon allotropes with monoclinic symmetry

“…After the above geometric structure optimization, elastic constant and phonon spectra calculations were done, also using CASTEP. There are 87 different new 3D silicon allotrope structures with monoclinic symmetry (excluding those with structural deformation or space group transformation) whose structures are different from those of monoclinic silicon allotrope structures predicted previously (Wang et al, 2014;Fan et al, 2016;Wei et al, 2019;Lee et al, 2016;Amsler et al, 2015). We further studied their structures and physical properties using first-principles calculations.…”

Theoretical study on structural and mechanical properties of Si-containing ternary transition metal nitrides M0.5Si0.5N (M = Ti, Zr, Hf)

“…The structure searching process for Ti 0.5 Si 0.5 N, Zr 0.5 Si 0.5 N and Hf 0.5 Si 0.5 N systems was performed in the pressure of 0-100 GPa, by the method of CALYPSO, 17,18 which has been fully conrmed as an reliable and effective structural searching approach. [19][20][21][22][23][24][25] We adopted 0, 30, 50 and 100 GPa as the searching pressure points. The crystal cell containing 1-4 formula units (f.u.)…”

A new direct band gap silicon allotrope o-Si32

“…They also found that h-Si6 is a semiconductor material with a direct band gap of 0.61 eV, further revealing excellent optical properties. Wei et al [15] found six new silicon phases via high-throughput calculations. They revealed that the six silicon allotropes are direct band gap semiconductor materials with band gap values ranging from 0.66 eV to 1.47 eV.…”