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Title: Properties of the exotic metastable ST12 germanium allotrope

Abstract

The optical and electronic properties of semiconducting materials are of great importance to a vast range of contemporary technologies. Diamond-cubic germanium is a well-known semiconductor, although other ‘exotic’ forms may possess distinct properties. In particular, there is currently no consensus for the band gap and electronic structure of ST12-Ge (tP12, P4 32 12) due to experimental limitations in sample preparation and varying theoretical predictions. Here we report clear experimental and theoretical evidence for the intrinsic properties of ST12-Ge, including the first optical measurements on bulk samples. Phase-pure bulk samples of ST12-Ge were synthesized, and the structure and purity were verified using powder X-ray diffraction, transmission electron microscopy, Raman and wavelength/energy dispersive X-ray spectroscopy. Lastly, optical measurements indicate that ST12-Ge is a semiconductor with an indirect band gap of 0.59 eV and a direct optical transition at 0.74 eV, which is in good agreement with electrical transport measurements and our first-principles calculations.

Authors:
 [1];  [2];  [3];  [4];  [2];  [2]
  1. Carnegie Institution of Washington, Washington, D.C. (United States); Yanshan Univ., Qinhuangdao (China)
  2. Carnegie Institution of Washington, Washington, D.C. (United States)
  3. Carnegie Institution of Washington, Washington, D.C. (United States); Center for High Pressure Science and Technology Advanced Research, Shanghai (China)
  4. Yanshan Univ., Qinhuangdao (China)
Publication Date:
Research Org.:
Carnegie Institution of Washington, Washington, D.C. (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1345973
Grant/Contract Number:
SC0001057
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; electronic devices; electronic properties and materials; solar cells

Citation Formats

Zhao, Zhisheng, Zhang, Haidong, Kim, Duck Young, Hu, Wentao, Bullock, Emma S., and Strobel, Timothy A. Properties of the exotic metastable ST12 germanium allotrope. United States: N. p., 2017. Web. doi:10.1038/ncomms13909.
Zhao, Zhisheng, Zhang, Haidong, Kim, Duck Young, Hu, Wentao, Bullock, Emma S., & Strobel, Timothy A. Properties of the exotic metastable ST12 germanium allotrope. United States. doi:10.1038/ncomms13909.
Zhao, Zhisheng, Zhang, Haidong, Kim, Duck Young, Hu, Wentao, Bullock, Emma S., and Strobel, Timothy A. Tue . "Properties of the exotic metastable ST12 germanium allotrope". United States. doi:10.1038/ncomms13909. https://www.osti.gov/servlets/purl/1345973.
@article{osti_1345973,
title = {Properties of the exotic metastable ST12 germanium allotrope},
author = {Zhao, Zhisheng and Zhang, Haidong and Kim, Duck Young and Hu, Wentao and Bullock, Emma S. and Strobel, Timothy A.},
abstractNote = {The optical and electronic properties of semiconducting materials are of great importance to a vast range of contemporary technologies. Diamond-cubic germanium is a well-known semiconductor, although other ‘exotic’ forms may possess distinct properties. In particular, there is currently no consensus for the band gap and electronic structure of ST12-Ge (tP12, P43212) due to experimental limitations in sample preparation and varying theoretical predictions. Here we report clear experimental and theoretical evidence for the intrinsic properties of ST12-Ge, including the first optical measurements on bulk samples. Phase-pure bulk samples of ST12-Ge were synthesized, and the structure and purity were verified using powder X-ray diffraction, transmission electron microscopy, Raman and wavelength/energy dispersive X-ray spectroscopy. Lastly, optical measurements indicate that ST12-Ge is a semiconductor with an indirect band gap of 0.59 eV and a direct optical transition at 0.74 eV, which is in good agreement with electrical transport measurements and our first-principles calculations.},
doi = {10.1038/ncomms13909},
journal = {Nature Communications},
number = ,
volume = 8,
place = {United States},
year = {Tue Jan 03 00:00:00 EST 2017},
month = {Tue Jan 03 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
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