Experimental observations of large changes in electron density distributions in β-Ge

Li, Rui; Liu, Jing; Popov, Dmitry; Park, Changyong; Meng, Yue; Shen, Guoyin

doi:10.1103/PhysRevB.100.224106

Title: Experimental observations of large changes in electron density distributions in $β - Ge$

Abstract

We report the electron density distributions in β-Ge have been experimentally determined at in situ high-pressure conditions using synchrotron diffraction techniques in a diamond anvil cell. Upon decompression, the electron density along the $$c$$ axis in tetragonal β-Ge displays a sudden drop at 10–11 GPa close to that of the structural α-β transition, while the β-Ge samples remain as single crystals until transforming to metastable Ge phases around 6.7–8.5 GPa. In contrast to the covalently bonded α-Ge that displays only a weak participation of $$d$$ electrons in the valence band under compression above 7.7 GPa, our experimental results suggest that a large change in $$d$$-orbital participation can occur in the β-Ge lattice which has mixed covalent and metallic bonding. The β-Ge below 10 GPa may display large fluctuations in electronic properties, which sheds light for exploring novel materials with intriguing electronic and optical properties.

Authors:

Li, Rui ^[1]; Liu, Jing ^[2]; Popov, Dmitry ^[3];

^[3]; Meng, Yue ^[3];

^[3]

Chinese Academy of Sciences (CAS), Beijing (China); Carnegie Inst. for Science, Washington, DC (United States)
Chinese Academy of Sciences (CAS), Beijing (China)
Argonne National Lab. (ANL), Argonne, IL (United States). HPCAT

Publication Date:: Thu Dec 19 00:00:00 EST 2019

Research Org.:: Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)

Sponsoring Org.:: National Natural Science Foundation of China (NSFC); China Scholarship Council (CSC); Chinese Academy of Sciences (CAS); USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:: 1607449

Grant/Contract Number:: AC02-06CH11357; 11634004; FG02-99ER45775; KJCX2-SWN20; KJCX2-SW-N03

Resource Type:: Accepted Manuscript

Journal Name:: Physical Review B

Additional Journal Information:: Journal Volume: 100; Journal Issue: 22; Journal ID: ISSN 2469-9950

Publisher:: American Physical Society (APS)

Country of Publication:: United States

Language:: English

Subject:: 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 36 MATERIALS SCIENCE

Citation Formats


                    Li, Rui, Liu, Jing, Popov, Dmitry, Park, Changyong, Meng, Yue, and Shen, Guoyin. Experimental observations of large changes in electron density distributions in β-Ge.  United States: N. p., 2019. 
Web.  doi:10.1103/PhysRevB.100.224106.

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                    Li, Rui, Liu, Jing, Popov, Dmitry, Park, Changyong, Meng, Yue, & Shen, Guoyin. Experimental observations of large changes in electron density distributions in β-Ge.  United States.  https://doi.org/10.1103/PhysRevB.100.224106

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                    Li, Rui, Liu, Jing, Popov, Dmitry, Park, Changyong, Meng, Yue, and Shen, Guoyin. Thu .  
"Experimental observations of large changes in electron density distributions in β-Ge".  United States.  https://doi.org/10.1103/PhysRevB.100.224106.  https://www.osti.gov/servlets/purl/1607449.

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@article{osti_1607449,

  title        = {Experimental observations of large changes in electron density distributions in β-Ge},

  author       = {Li, Rui and Liu, Jing and Popov, Dmitry and Park, Changyong and Meng, Yue and Shen, Guoyin},

  abstractNote = {We report the electron density distributions in β-Ge have been experimentally determined at in situ high-pressure conditions using synchrotron diffraction techniques in a diamond anvil cell. Upon decompression, the electron density along the $c$ axis in tetragonal β-Ge displays a sudden drop at 10–11 GPa close to that of the structural α-β transition, while the β-Ge samples remain as single crystals until transforming to metastable Ge phases around 6.7–8.5 GPa. In contrast to the covalently bonded α-Ge that displays only a weak participation of $d$ electrons in the valence band under compression above 7.7 GPa, our experimental results suggest that a large change in $d$-orbital participation can occur in the β-Ge lattice which has mixed covalent and metallic bonding. The β-Ge below 10 GPa may display large fluctuations in electronic properties, which sheds light for exploring novel materials with intriguing electronic and optical properties.},

  doi          = {10.1103/PhysRevB.100.224106},

  journal      = {Physical Review B},

  number       = 22,

  volume       = 100,

  place        = {United States},

  year         = {Thu Dec 19 00:00:00 EST 2019},

  month        = {Thu Dec 19 00:00:00 EST 2019}

}

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Title: Experimental observations of large changes in electron density distributions in β - Ge

Abstract

Citation Formats

High-pressure phase transitions in diamond and zinc-blende semiconductors journal, January 1987

Erratum: Phase transitions in InSb at pressures up to 5 GPa journal, October 1993

Theoretical study of Raman modes in high-pressure phases of Si, Ge, and Sn journal, August 1993

Novel metastable metallic and semiconducting germaniums journal, March 2013

High pressure studies of Ge using synchrotron radiation journal, June 1983

A short history of SHELX journal, December 2007

The Effect of Micro-Strain and Pressure Medium on the High-Pressure Phase of GaSb journal, January 1999

High-pressure and high-temperature study of phase transitions in solid germanium journal, November 2003

Theory of static structural properties, crystal stability, and phase transformations: Application to Si and Ge journal, November 1982

High-pressure phases of germanium journal, December 2000

Hexagonal (Wurtzite) Silicon journal, August 1977

β − tin → I m m a → sh Phase Transitions of Germanium journal, March 2011

Electronic structure and metallization of silicon journal, February 1984

High-pressure phases of group-IV, III–V, and II–VI compounds journal, July 2003

Density-functional calculations of the structural properties of tin under pressure journal, September 1993

Pressure-induced changes in the electron density distribution in α-Ge near the α-β transition journal, August 2015

Pressure-induced phase transitions in amorphous and metastable crystalline germanium by Raman scattering, x-ray spectroscopy, and ab initio calculations journal, September 2009

Covalent-Ionic and Covalent-Metallic Transitions of Tetrahedrally Coordinated A N B 8 − N Crystals Under Pressure journal, November 1971

Kinetic Origin of Divergent Decompression Pathways in Silicon and Germanium journal, April 2013

New developments in laser-heated diamond anvil cell with in situ synchrotron x-ray diffraction at High Pressure Collaborative Access Team journal, July 2015

Error Maps in Charge and Momentum Density Studies by the Maximum Entropy Methods journal, September 2003

Phase-Transition Studies of Germanium to 1.25 Mbar journal, May 1986

Theory of the high-pressure structural phase transitions in Si, Ge, Sn, and Pb journal, April 2006

Controlled formation of metastable germanium polymorphs journal, April 2014

The maximum-entropy method in charge-density studies: aspects of reliability journal, May 1993

Theory of covalent-metallic phase transitions of Si, Ge and Sn under pressure journal, October 1972

Stability and crystal structure of BC8 germanium journal, October 1993

Integration, scaling, space-group assignment and post-refinement journal, January 2010

XDS journal, January 2010

Germanium at high pressures journal, July 1986

Angle calculations for 3- and 4-circle X-ray and neutron diffractometers journal, April 1967

Electronic structure, equation of state, and lattice dynamics of low-pressure Ge polymorphs journal, August 2012

Crystal Structures at High Pressures of Metallic Modifications of Silicon and Germanium journal, February 1963

Title: Experimental observations of large changes in electron density distributions in $β - Ge$

High-pressure phase transitions in diamond and zinc-blende semiconductors
journal, January 1987

Erratum: Phase transitions in InSb at pressures up to 5 GPa
journal, October 1993

Theoretical study of Raman modes in high-pressure phases of Si, Ge, and Sn
journal, August 1993

Novel metastable metallic and semiconducting germaniums
journal, March 2013

High pressure studies of Ge using synchrotron radiation
journal, June 1983

A short history of SHELX
journal, December 2007

The Effect of Micro-Strain and Pressure Medium on the High-Pressure Phase of GaSb
journal, January 1999

High-pressure and high-temperature study of phase transitions in solid germanium
journal, November 2003

Theory of static structural properties, crystal stability, and phase transformations: Application to Si and Ge
journal, November 1982

High-pressure phases of germanium
journal, December 2000

Hexagonal (Wurtzite) Silicon
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$β − tin \to I m m a \to sh$ Phase Transitions of Germanium
journal, March 2011

Electronic structure and metallization of silicon
journal, February 1984

High-pressure phases of group-IV, III–V, and II–VI compounds
journal, July 2003

Density-functional calculations of the structural properties of tin under pressure
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Pressure-induced changes in the electron density distribution in α-Ge near the α-β transition
journal, August 2015

Pressure-induced phase transitions in amorphous and metastable crystalline germanium by Raman scattering, x-ray spectroscopy, and ab initio calculations
journal, September 2009

Covalent-Ionic and Covalent-Metallic Transitions of Tetrahedrally Coordinated $A^{N} B^{8 - N}$ Crystals Under Pressure
journal, November 1971

Kinetic Origin of Divergent Decompression Pathways in Silicon and Germanium
journal, April 2013

New developments in laser-heated diamond anvil cell with in situ synchrotron x-ray diffraction at High Pressure Collaborative Access Team
journal, July 2015

Error Maps in Charge and Momentum Density Studies by the Maximum Entropy Methods
journal, September 2003

Phase-Transition Studies of Germanium to 1.25 Mbar
journal, May 1986

Theory of the high-pressure structural phase transitions in Si, Ge, Sn, and Pb
journal, April 2006

Controlled formation of metastable germanium polymorphs
journal, April 2014

The maximum-entropy method in charge-density studies: aspects of reliability
journal, May 1993

Theory of covalent-metallic phase transitions of Si, Ge and Sn under pressure
journal, October 1972

Stability and crystal structure of BC8 germanium
journal, October 1993

Integration, scaling, space-group assignment and post-refinement
journal, January 2010

XDS
journal, January 2010

Germanium at high pressures
journal, July 1986

Angle calculations for 3- and 4-circle X-ray and neutron diffractometers
journal, April 1967

Electronic structure, equation of state, and lattice dynamics of low-pressure Ge polymorphs
journal, August 2012

Crystal Structures at High Pressures of Metallic Modifications of Silicon and Germanium
journal, February 1963