Context and results This study investigates the structural evolution and superconducting mechanisms of arsenic (As) under pressures ranging from 0 to 400 GPa using first-principles calculations. The phase transition sequence aligns with experimental data (<InlineEquation ID="IEq1"> <EquationSource Format="TEX">$R\overline{3 }m$</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mi>R</mi> <mover> <mn>3</mn> <mo>¯</mo> </mover> <mi>m</mi> </mrow> </math></EquationSource> </InlineEquation>-<InlineEquation ID="IEq2"> <EquationSource Format="TEX">$Pm\overline{3 }m$</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mi>P</mi> <mi>m</mi> <mover> <mn>3</mn> <mo>¯</mo> </mover> <mi>m</mi> </mrow> </math></EquationSource> </InlineEquation>-HG phase-<InlineEquation ID="IEq3"> <EquationSource Format="TEX">$Im\overline{3 }m$</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mi>I</mi> <mi>m</mi> <mover> <mn>3</mn> <mo>¯</mo> </mover> <mi>m</mi> </mrow> </math></EquationSource> </InlineEquation>), with the As phase demonstrating stability between 100 and 400 GPa. At 100 GPa, the As-IV (<InlineEquation ID="IEq4"> <EquationSource Format="TEX">$Im\overline{3 }m$</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mi>I</mi> <mi>m</mi> <mover> <mn>3</mn> <mo>¯</mo> </mover> <mi>m</mi> </mrow> </math></EquationSource> </InlineEquation>) phase exhibits a superconducting transition temperature (Tc) of 5.5 K, driven by As-p orbital hybridization, which enhances the density of states at the Fermi level and strengthens electron-phonon coupling. However, as pressure increases, electronic structure changes suppress superconductivity, with a shift in the VHS peak and a decrease in p-orbital contributions, leading to a Tc drop near zero at 400 GPa. These results suggest a potential phase transition above 400 GPa and offer insights for future high-pressure studies of arsenic. Computational methods The electronic properties are calculated using density functional theory (DFT) implemented in the CASTEP code, employing the projector augmented-wave (PAW) method for the plane-wave expansion. The exchange-correlation interaction is described using the PBE functional within the generalized gradient approximation (GGA). Electron-phonon coupling (EPC) and superconducting properties are computed with the QUANTUM ESPRESSO code, utilizing the optimized norm-conserving Vanderbilt pseudopotential (ONCVPSP).

Structural evolution and superconductivity of arsenic under high pressure

期刊论文
发表日期：

2026年4月13日

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Lan-Xi Luo,
Wen-Guang Li,
Zheng-Tang Liu,
Juan Ren

摘要

Context and results

This study investigates the structural evolution and superconducting mechanisms of arsenic (As) under pressures ranging from 0 to 400 GPa using first-principles calculations. The phase transition sequence aligns with experimental data ( $R\overline{3 }m$ $R \bar{3} m$ - $Pm\overline{3 }m$ $P m \bar{3} m$ -HG phase- $Im\overline{3 }m$ $I m \bar{3} m$ ), with the As phase demonstrating stability between 100 and 400 GPa. At 100 GPa, the As-IV ( $Im\overline{3 }m$ $I m \bar{3} m$ ) phase exhibits a superconducting transition temperature (T_c) of 5.5 K, driven by As-p orbital hybridization, which enhances the density of states at the Fermi level and strengthens electron-phonon coupling. However, as pressure increases, electronic structure changes suppress superconductivity, with a shift in the VHS peak and a decrease in p-orbital contributions, leading to a T_c drop near zero at 400 GPa. These results suggest a potential phase transition above 400 GPa and offer insights for future high-pressure studies of arsenic.

Computational methods

The electronic properties are calculated using density functional theory (DFT) implemented in the CASTEP code, employing the projector augmented-wave (PAW) method for the plane-wave expansion. The exchange-correlation interaction is described using the PBE functional within the generalized gradient approximation (GGA). Electron-phonon coupling (EPC) and superconducting properties are computed with the QUANTUM ESPRESSO code, utilizing the optimized norm-conserving Vanderbilt pseudopotential (ONCVPSP).