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Updated: Apr 24, 2026

Atmospheric Pressure Fabrication of Large-Sized Single-Layer Rectangular SnSe Flakes
Published on: March 21, 2018
Bulk signatures of pressure-induced band inversion and topological phase transitions in Pb(1-x)Sn(x)Se
Xiaoxiang Xi1, Xu-Gang He2, Fen Guan3
1Photon Sciences, Brookhaven National Laboratory, Upton, New York 11973, USA.
Abstract:
The characteristics of topological insulators are manifested in both their surface and bulk properties, but the latter remain to be explored. Here we report bulk signatures of pressure-induced band inversion and topological phase transitions in Pb(1-x)Sn(x)Se (x=0.00, 0.15, and 0.23). The results of infrared measurements as a function of pressure indicate the closing and the reopening of the band gap as well as a maximum in the free carrier spectral weight. The enhanced density of states near the band gap in the topological phase gives rise to a steep interband absorption edge. The change of density of states also yields a maximum in the pressure dependence of the Fermi level. Thus, our conclusive results provide a consistent picture of pressure-induced topological phase transitions and highlight the bulk origin of the novel properties in topological insulators.
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